"Lily C.A.T." is a 1987 science fiction anime OVA directed by Hisayuki Toriumi, blending elements of space horror and mystery. The narrative unfolds aboard the deep-space exploration vessel Saldes, which is on a 20-year mission to investigate a distant planet. Due to the effects of time dilation, only a few months pass for the crew, while decades elapse on Earth. The crew consists of a diverse group, including Captain Mike Hamilton, medical officer Nancy Strider, security officer Dick Berry, and engineer Jimmy, among others.

The story begins with the crew awakening from suspended animation to find their ship damaged and their mission compromised. As they attempt to repair the vessel and continue their journey, strange occurrences begin to plague the crew. A mysterious alien organism infiltrates the ship, mimicking the appearance and memories of deceased crew members. This shapeshifting entity, referred to as Lily C.A.T., begins systematically eliminating the crew, creating an atmosphere of paranoia and mistrust.

The crew's attempts to identify and combat the alien threat are complicated by internal conflicts and the realization that the organism can manipulate their perceptions. As the body count rises, the survivors struggle to discern reality from illusion, questioning the true nature of their mission and the intentions of their superiors. The narrative explores themes of isolation, survival, and the fragility of human identity in the face of an incomprehensible alien presence.

The climax reveals that the alien organism was inadvertently brought aboard during a previous mission, and its presence on the Saldes is a result of corporate negligence. The final confrontation pits the remaining crew members against the fully manifested Lily C.A.T., leading to a tense and ambiguous resolution. The OVA concludes with a haunting reflection on the consequences of humanity's ventures into the unknown, leaving the fate of the survivors uncertain.

"Lily C.A.T." is notable for its atmospheric tension, influenced by classic science fiction and horror films such as "Alien" and "The Thing." The characters are archetypal, serving to highlight the psychological and existential dilemmas posed by the narrative. The OVA's concise runtime and focused storytelling make it a compelling entry in the genre, offering a blend of suspense, action, and speculative themes.