Meet Testament: the premier caretaker android for the future. Not only were they designed to care for the wellbeing of dozens of interstellar passengers; explorers, scientists, poets, and artists - they have also downloaded millennia of religious texts and liturgies to best serve the members of a religious commune that make up the bulk of their human charges. These members of the Order of the Abundant Grace of the Cosmic Christ, having already chosen a monastic and scholarly life, are ideal for their mission: a one-way voyage to discover all they can about a miraculous far-flung planet capable of life and, by choice, not repopulate. Soon, only Sister Judith remains on the distant planet, facing decades of life alone with her caretaker and no other human company. Struggling with faith and despair, she seeks purpose, or perhaps something else, in a sudden research trip into hazardous territory. Testament tries to carry out their directives, while staring down their own immortality, and questioning their place in a spiritual infinity equipped with the knowledge and traditions of people who could never have imagined a being like them.