Washu explains to Tenchi that two individuals became caught in a dimensional warp during one of her experiments. She tasks him with returning them to their original locations and sends him back in time to accomplish this. Tenchi arrives in a feudal-era setting and immediately encounters a young girl. This child is a younger version of Momo, the student council president from the present day. Momo does not recognize Tenchi and is confused by his sudden appearance. Tenchi uses his mobile phone to show her images, and they begin searching for her missing partner. The episode establishes itself as the first chronological installment in the series, revealing events that precede Tenchi's arrival at the academy. The setting shifts entirely away from the school environment to focus on this past time period. Tenchi's mission gains clarity as he understands he must locate and return the displaced individuals to correct the timeline. The search leads them through the unfamiliar historical landscape, with young Momo relying on Tenchi's guidance and technology. Their investigation sets the stage for encounters with other characters from the present who also exist in this era, directly leading into the next phase of the retrieval mission.

Tenchi flees from the student council office wearing only his boxers and carrying his uniform. He searches for a place to dress and enters the old school building, believing it to be abandoned. After putting on his clothes, he hears pickaxe sounds from beneath a classroom and falls through a trap door. Tenchi discovers an extensive excavation tunnel led by Science Club president Yuki Fuka, who works with the timid Rui Aoi. Yuki's faction digs aggressively beneath the school, searching for an unknown object to use against the Student Council. Tenchi accidentally dislodges rocks while observing, alerting Beni Kinojyou to his presence. Beni captures Tenchi and brings him to Yuki, who suspects him of being a spy. The Science Club members restrain Tenchi on a table, remove his clothing, and place a ball gag in his mouth. Yuki prepares to interrogate Tenchi physically while Rui reacts with embarrassment to the proceedings. Mihoshi makes a brief vocal cameo, though her face remains unseen during the encounter. The episode establishes the Science Club's underground operation as a direct challenge to Student Council authority, with Tenchi caught helplessly between the two factions. Tenchi remains bound to the table as Yuki closes in, leaving his fate and the purpose of the excavation unresolved.

Tenchi Masaki carries a stack of old club records to the supply shed behind the school. Momoyo and Hachiko follow him after noticing his abrupt departure from class. Inside the shed, Tenchi brushes against a cylindrical container marked with unfamiliar symbols. The container opens and releases a small hovering drone. The drone scans Tenchi and identifies him as a temporary liaison for the Galactic Academy. Momoyo steps forward and seizes the drone before it can transmit a confirmation signal. She explains that similar devices have attempted to contact students before, each time leading to unwanted interstellar obligations. Hachiko disables the drone’s transmitter with a quick tap to its casing. Tenchi demands to know why they are hiding such technology on school grounds. Momoyo responds only that the principal placed the container there years ago as a precaution. The three leave the shed, and Momoyo orders Tenchi to keep what he saw secret. In the hallway, the principal watches from a window and makes a quiet call to an off‑world contact, stating that the liaison protocol has been triggered earlier than expected. The drone reactivates silently in the locked shed, its beacon now transmitting a continuous location signal.

Tenchi Masaki returns to the simple inn where he is staying with Sasami, Ayeka, and Ryoko. He has just survived his first day as a student teacher at the all-girls Junai Academy, a mission assigned to him by the scientist Washu. Sasami, Ayeka, and Ryoko greet him and pledge their support for his undercover task. Shortly after his arrival, Washu sends a box containing armor and protective charms, insisting that Tenchi will need them for the job ahead. The episode provides a respite from the chaotic encounters Tenchi faced at the academy, which included aggressive members of both the student council and the science club. The tone shifts from the school's high-energy conflicts to the quieter, domestic dynamic of the Masaki household. This return home allows the traditional cast to reaffirm their roles as his allies. Washu's delivery of equipment injects a new element of preparation, suggesting the mission's stakes are higher than a simple teaching placement. The episode establishes a base of operations for Tenchi and reinforces the support system available to him outside of the academy. The narrative prepares for the next phase of his mission, with the clear implication that the coming days at the school will require the defensive items Washu has provided.

Tenchi Masaki accompanies Momo to a sealed section of the school after her ship detects an energy signature matching Jurai technology. They find a hidden laboratory containing stasis pods and data logs detailing long-term observation of Tenchi’s bloodline. An automated security system activates, sealing the room and releasing a series of combat drones. Momo disables the drones by interfacing directly with the facility’s mainframe, exposing her non-human physiology to Tenchi. Ayeka emerges from the shadows and confirms she has been tracking their movements since the signal first appeared. She reveals the laboratory was established by the Jurai royal family to monitor Tenchi’s developing abilities without his knowledge. The data logs indicate the observation period is connected to a pending galactic treaty negotiation involving Earth. Tenchi demands an explanation, but Ayeka states she is bound by orders not to disclose the full scope of the operation. The school principal arrives unannounced, carrying a sealed order that overrides Ayeka’s authority and reassigns her to off-world duty. Ayeka leaves without further comment, and the principal orders Tenchi to return to his regular duties as if nothing occurred. Momo warns Tenchi that the principal’s intervention suggests a third faction is now directing the observation program.

The episode depicts the immediate preparations for the school's Sports Day festival. The female students are shown changing into their gym uniforms, an event that highlights the differing attitudes among them, with some like Hana and Rui adjusting their clothing for style while Touri is noted to require little change to her standard appearance. Student Council President Momo addresses the assembled students, cheerfully but firmly ordering everyone to prioritize having fun during the upcoming events. In the teachers' office, the instructor Kurihara provides Tenchi with his assignment for the festival: he is to serve as a referee and is fitted with a suit of armor for the role. Kurihara informs Tenchi that the sporting competitions are based on local traditions, hinting at unconventional or hazardous activities without providing specific details. The entire student body is later gathered in a formal assembly, arranged in disciplined rows as if for a military formation. Kurihara addresses the students from a podium and formally announces the stakes for the Sports Day competitions. The winning club will receive additional materials, increased funding, and a highly unusual reward: the services of Tenchi as a personal servant for an entire day. This announcement reveals that Tenchi himself is hearing the terms regarding his own servitude for the first time, establishing a personal conflict for him and raising the potential for his future mistreatment. The episode concludes with the festival about to begin, the rules set, and Tenchi facing an uncertain personal cost depending on the outcomes of the games.

This episode is a recap that summarizes the narrative developments from episodes sixteen through nineteen. The summary revisits key moments from the school festival arc, including Tenchi's unexpected participation in the Drama Club play and his subsequent involvement in the beauty contest. It also covers the ongoing conflict between the Student Council and the Science Club, highlighting the competition between the two factions during the festival events. Concurrently, the recap revisits the space-based subplot involving Ryouko's return to piracy and the undercover mission undertaken by Galaxy Police detectives Kiyone and Mihoshi. The detectives had infiltrated Ryouko's crew, the "Paper Bag Gang," with the objective of apprehending her. Ryouko and her associate Hotsuma quickly discerned the detectives' true identities but chose to entertain themselves by subjecting Kiyone and Mihoshi to a series of humiliating trials for the gang's amusement. Despite the initial mission objective, Kiyone's motivation shifted from making an arrest to persuading Ryouko to return to the Masaki household, driven by concern for Tenchi. The detectives' efforts to bond with Ryouko are depicted, including a conversation in a replica of Tenchi's living room where they discuss personal matters. Hotsuma, observing this interaction secretly, is shown to disapprove of the growing camaraderie and decides to alert the Galaxy Police to Ryouko's location, setting up a future confrontation. The Earth-based segments of the recap focus on the interpersonal dynamics at school, particularly the growing rapport between Tenchi and his classmate Sakuya, which draws notice from their peers. The episode concludes by bringing these summarized threads together, establishing Ryouko's emotional turmoil regarding Tenchi and Sakuya, and Hotsuma's impending betrayal as the immediate consequence that will drive the next phase of the narrative.

The sports festival at Saint Gassan Academy continues with the traditional cavalry battle event. The competition takes an unconventional turn when the blue team, representing the science club, fields a mecha robot named Gouriki-kun as their mounted unit. Tenchi Masaki, serving as the teacher and referee for the games, rules that the robotic entry is permitted to participate, establishing the parameters for the match. The white team, composed of student council members, initially protests this decision but ultimately faces the mechanical opponent in the competition. During the heated contest, Yuki creates a distraction by placing a fake spider on Rui, who reacts with intense fear. This moment of chaos on the blue team provides an opening for the white team to secure victory in the cavalry battle. The rivalry between the two factions continues as the festival progresses, with tensions remaining high following the white team's win. The event showcases the students' willingness to employ unconventional tactics, both through Yuki's psychological strategy and the science club's technological approach to the traditional competition. The episode contributes to the ongoing school festival arc, maintaining the focus on the interpersonal dynamics between the student council members and the other students under Tenchi's supervision.

The sports festival at Junai Academy continues late into the night, extending well beyond its scheduled conclusion. The competition eventually narrows down to a quiz format, which appears to determine an overall winner. However, Yuki, the representative of the white team, immediately cries foul over her team's loss and disputes the outcome. Hachiko, representing the opposing side, accepts Yuki's challenge to continue the competition. This agreement prolongs the festival further, as a series of unscheduled, impromptu events replace the official program. The characters' motivations center on inter-club rivalry and the stubborn refusal to accept defeat, driving the extended competition. As the night wears on, the prolonged events begin to take a toll on the participants. Momo, the student council president, falls asleep while positioned against Tenchi during one of the ongoing contests. This action draws a sharp, jealous reaction from Ryoko, who observes the moment. The episode concludes with a scene at the Masaki household, where Sasami excitedly informs Tenchi about his impending new duty. Starting the following day, Tenchi is required to work as a live-in supervisor at the girls' dormitory, a development that fills him with evident apprehension. The immediate consequence of the episode's events is this shift in Tenchi's assignment, setting the stage for his interactions within the dormitory environment.

Tenchi assumes his new duties as the supervisor of the girls' dormitory, a responsibility he approaches with visible apprehension. Upon his arrival, the residents greet him warmly, which contrasts sharply with his initial dread. Student Council President Momo Kawanagare provides Tenchi with a tour of the dormitory facilities. During the tour, they encounter Hana in a state of partial undress, wearing only an unbuttoned shirt and undergarments, causing Tenchi significant embarrassment. Beni Kinojyou subsequently appears, covered only by a towel as she heads to the bath, and expresses annoyance at Tenchi's flustered reaction to the situation. The relaxed attitudes of the residents toward modesty within the dorm create a recurring source of discomfort for Tenchi. Meanwhile, Science Club members Yuki and Rui attempt to execute their plan to recruit Tenchi as an ally for their faction. Their scheming, however, appears to produce the opposite effect, potentially undermining their objective. The episode establishes the dormitory as a new primary setting and explores the cultural clash between Tenchi's expectations and the residents' behavior. The character dynamics shift as Tenchi must navigate this unfamiliar environment while the various factions continue their efforts to gain his favor or cooperation.

Tenchi is tasked with cleaning the girls' bath, a routine chore that quickly escalates into a complicated situation. His work is interrupted when Momo and several other students enter to bathe, forcing him to hastily conceal himself to avoid a scandal. Momo discovers Tenchi in his hiding spot but makes a quick decision to hide him herself rather than expose his presence to the others. As the Student Council members discuss school matters in the bath, Tenchi remains hidden and inadvertently becomes an eavesdropper on their conversation. The discussion among the bathing students reveals crucial information about the rogue Science Club's activities. Tenchi learns that the Science Club is actively searching for a treasure, confirming that their excavation projects and unconventional behavior have a specific objective. This overheard conversation provides Tenchi with a clearer understanding of the faction's motivations and goals. The immediate consequence of this incident is Tenchi's acquisition of actionable intelligence regarding the conflict between the student groups. Momo's choice to protect Tenchi, despite the risk to her own position, deepens the implicit trust and complicated dynamic between them. The episode concludes with Tenchi in possession of this new information, which will shape his future interactions and decisions concerning the Science Club. The events in the bathhouse thus serve as a pivotal moment for plot progression, shifting the focus from daily school life to the underlying mystery.

Tenchi Masaki discovers Yuki and Rui of the Science Club awake past curfew, secretly eating instant ramen in their dorm room. Rather than reprimanding them, he opts to join them, leading to an informal conversation. During this meeting, Tenchi learns that their club's advisor, Beni, is not present and typically spends her nights sleeping on the school's rooftop, highlighting her separation from the group's activities. Yuki discusses her passion for building mechanisms, specifically her mecha, though she admits to not understanding the scientific principles that make her creations function. Their conversation is interrupted when a detection device, referred to as the Gouriki-kun head, activates, signaling a potential discovery. The trio immediately proceeds to an underground location to investigate, hoping to find the treasure the Science Club has been seeking. However, their excavation effort yields no results, as the location proves to be empty. The failed search leaves the club's objective unfulfilled and the nature of what they are hunting for still a mystery. Beni's continued absence from these core club activities and her choice to isolate herself on the roof reinforces her enigmatic presence within the school. The episode primarily functions to provide subtle background on the Science Club members' dynamics and their ongoing, fruitless search.

The episode opens with a flashback set on the planet Jurai, depicting Kurenai as a young orphaned girl being released from imprisonment by the royal family. She is tasked with the care of the infant princess Momo, establishing the origin of the bond between the two characters. The scene transitions to a later moment where a now-adolescent Momo affectionately calls Kurenai 'Beni' as they prepare to board a ship that will take them to a distant 'destiny'. This voyage ultimately leads to the crash-landing on Earth seen in earlier episodes. In the present-day timeline, the narrative continues from the previous episode's cliffhanger with Tenchi locating Beni inside her crashed ship. Tenchi activates a program on his smartphone, intending to use it to return himself and Momo to their own time. Instead of executing the return function, the program malfunctions and generates a new dimensional rift. This tear in the sky generates a powerful suction force that pulls both Tenchi and the young Momo into it. During the chaos of this abduction, Tenchi loses hold of his smartphone, which falls into a crevice and is left behind in the past. The episode concludes with the two protagonists being drawn into the unknown dimension, leaving their fate uncertain and their means of return lost.

Tenchi Masaki seeks out Beni on the school rooftop for a private conversation, acting on his growing concerns about her. Beni reveals her awareness that she is not a normal human and, recalling Tenchi's prior ability to subdue a rogue mecha, directly challenges him to a genuine fight. As Beni initiates her charge, Momo Kawanagare arrives on the scene, prompting Tenchi to quickly maneuver both girls to safety on the ground below. Beni expresses frustration that the confrontation was interrupted, a feeling that intensifies when she experiences a sudden, involuntary memory flash upon physical contact with Momo's hand. The moment is cut short by the arrival of Ms. Kurihara, who discovers Tenchi with two female students after hours and escorts him away for disciplinary action. The episode confirms that the Beni of the present day is the same individual from the flashback sequences on the planet Jurai. Her fragmented memory and instinctive reaction to Momo provide direct evidence of their previously established, yet forgotten, connection. Tenchi's intervention prioritizes the students' safety over engaging in the fight Beni sought. The unresolved tension between Beni and Momo, coupled with Tenchi's punishment, leaves the immediate consequences of the rooftop encounter pending.

Tenchi is occupied with repairing a hole in the roof of the boys' dormitory. At the girls' dorm, Aeka and Sasami prepare a barbecue, with Ryoko present primarily for the food. The group extends an invitation to the four members of the Student Council. The three members of the Science Club also arrive, and Momo suggests they join the gathering, advocating for the more the merrier. The episode centers on this informal cookout, providing a setting for character interaction away from the usual school conflicts. The shared meal allows for moments of casual conversation and camaraderie among the students and Tenchi. Brief hints are woven into the episode suggesting that Momo may have experienced significant solitude in the past. These subtle indications provide a small amount of background context for her character without becoming a central focus of the episode's events. The barbecue scene itself serves as the primary narrative thread, with the characters' various personalities emerging through their interactions over food. The episode functions as a slice-of-life interlude, allowing the ensemble cast to simply spend time together. It advances no major plot points or conflicts, instead focusing on the dynamics between the characters during a moment of relaxation.

This episode provides essential background information that recontextualizes the series' premise up to this point. The narrative reveals that the events depicted in the first twenty-nine episodes are the result of a failed mission by Tenchi. It is disclosed that Momo, and presumably Beni, are temporal castaways whom Tenchi was originally sent into the past to rescue. The mission failed when another temporal rift opened, returning Tenchi to Washuu's lab while Momo and Beni ended up in the present day at Junai High. Upon Tenchi's return, Washuu convenes a family meeting with Ryoko, Aeka, and Sasami to formulate a new strategy. The new plan devised by Washuu involves Tenchi infiltrating Junai High School under the guise of a student teacher to gather information for a second rescue attempt. This explains Tenchi's arrival at the school as seen in the first episode and his subsequent interactions with the students. The episode functions as a narrative turning point, shifting from the daily school hijinks to a more focused mission-driven plot. It clarifies the motivations of the central characters, particularly Tenchi's role as more than just a student teacher. The immediate consequence of this revelation is that Tenchi, along with Ryoko, Aeka, and Sasami, will now work to support the mission from within the school environment. This new understanding informs the narrative direction for the remaining episodes of the series. The episode was directed by Ryōichi Kuraya, with animation direction by Hiroyuki Ochi and Kazuhiko Yokota.

Washu communicates with the Science Club through an obelisk, chastising them for their failure to locate the treasure and threatening to make the robot Gouriki-kun self-destruct. This ultimatum prompts Beni Kinojyou to visit Tenchi Masaki's residence, where she humbly requests his assistance and the help of the other girls living there. Tenchi and his companions subsequently accompany Beni to the underground excavation site beneath the school. Upon arrival, the group is surprised to find Mihoshi already present at the dig location. Mihoshi reveals she is working undercover to investigate temporal disturbances and the nature of the artifact the Science Club seeks. Meanwhile, back at the academy, teacher Kurihara informs Hana Saryu and Hachiko of the Student Council that the Science Club has effectively taken Tenchi. The discovery of Tenchi's smartphone, which he lost during his time in the past, provides a new clue linking the current events to his earlier mission. The Student Council reacts with alarm to the news of Tenchi's abduction and Sasami's apparent involvement. As tensions rise between the two school clubs, the robot Gouriki-kun is deployed to hold off an assault by the Student Council, allowing the Science Club to continue their excavation work. The episode establishes Mihoshi's official role in the investigation and sets the stage for a direct confrontation between the Student Council and the Science Club over Tenchi and the ongoing dig.

The episode opens with the Student Council in a state of panic following the abduction of Tenchi and Sasami by the Science Club. Their distress highlights the personal connection they have developed with their teacher, and the immediate consequence of the previous episode's cliffhanger is the council's inability to locate him. Meanwhile, deep within the underground excavation site, Tenchi and the others receive a briefing from Mihoshi, who reveals she is working undercover to investigate temporal disturbances linked to the treasure the Science Club seeks. Her presence adds a layer of official authority to the escalating conflict, suggesting the situation has implications beyond the school grounds. The arrival of Yuki and Rui at Tenchi's location introduces a pivotal piece of evidence: Tenchi's smartphone, which he lost during his initial mission in the past. Yuki manages to power on the 1300-year-old device, having cracked its password, and the screen displays a wallpaper photograph of Tenchi and Sasami together at a beach. This visual proof of a connection between the two, existing across centuries, immediately captures the attention of everyone present and shifts the focus of the investigation. The photograph becomes a source of considerable tension, as Aeka and Ryoko react with visible displeasure, interpreting the image as evidence of an inappropriate relationship. Their personal jealousy momentarily overshadows the larger mystery, creating a conflict among the rescuers. Concurrently, the Student Council launches an assault on the excavation site in an effort to retrieve their teacher, only to be held at bay by the powerful robot Gouriki-kun. The robot's successful defense prevents the council from intervening, allowing the standoff between the two factions to continue. The episode concludes with the mystery deepening: the true nature of the treasure remains obscured, and the discovery of the photograph complicates the motivations of those trying to rescue Tenchi, adding interpersonal discord to the existing external threats.

The Science Club and its allies launch an assault on the abandoned school building to buy time for Tenchi's excavation. Gouriki is overpowered by Hana and Hachiko, allowing Momo and Touri to gain entry to the structure. Yuki and Rui volunteer to hold off the Student Council, citing the treasure's importance to Beni, but Ryoko and Aeka take over the defensive position instead. Momo and Touri fall through a trap door into the dig site, where Touri lands on Tenchi and Momo is caught by Beni. The recovery of Tenchi's old smartphone from the excavation triggers an immediate reaction. Above ground, Ryoko confronts Hachiko while Aeka engages Hana, the conflict stemming from the Student Council's attempt to interfere with the Science Club's objective. Aeka's motivation is momentarily influenced by her irritation at being addressed as "obasan" by Hana. The battles serve as a diversion to protect the ongoing treasure hunt in the ruins below. The episode establishes a direct confrontation between the two school factions, with the former antagonists now working together against the Student Council. The discovery of the smartphone sets the stage for subsequent events, as its activation hints at larger forces at play in the search for the buried artifact.