Brother Dusk reflects on his legacy as he prepares for ascension. The Foundation arrives on Terminus and finds a mysterious object.

Brother Day meets Zephyr Halima—a would-be leader who opposes the Empire. Brother Dusk grows suspicious of Brother Dawn.

The Anacreons and their hostages board the fabled Invictus warship. The bond between Brother Dawn and Azura intesifies.

Brother Day embarks on a journey that no other Cleon has ever attempted. Salvor prepares to make the ultimate sacrifice to return home.

Hoping to find some answers, Ava puts her faith in science. Meanwhile, Cardinal Duretti’s machinations sow seeds of dissension inside the Order.

Secrets are revealed and a Sister Warrior mysteriously returns to the fold as Ava and her allies attempt to keep a sacred object out of the wrong hands.

Charlotte grapples with reality; Dolores and Caleb begin to form a key partnership.