Alicia, a time traveler from the 30th century, visits Satoru, a young religious student living in 2403 AD. She initiates their joint journey through time to explore significant historical and religious events across eras. A malfunction causes them to witness unplanned yet pivotal episodes: Hermes battling enemies, Moses parting the Red Sea, Shakyamuni Buddha performing miracles, Jesus Christ's death and resurrection, and the enlightenment of the Chinese monk Chih-i.

Throughout these experiences, Alicia serves as Satoru's observer and guide. She teaches him the connections between these historical figures and events, revealing how these individuals and all humanity interconnect within the broader flow of time and spiritual history. Alicia's background from the distant future places these events within a larger temporal framework. Her interactions reveal the underlying unity across different religious traditions and historical epochs through direct observation.

The journey emphasizes universal connection and spiritual continuity across civilizations. Alicia's purpose centers on imparting this perspective to Satoru, framing humanity's diverse religious expressions as part of a cohesive whole. Her character remains unchanged, functioning as a catalyst for Satoru's comprehension of humanity's shared spiritual legacy. Alicia's mother is acknowledged within the narrative, with no further familial details explored. She is defined by her role in enabling this educational journey through critical moments of religious history.