Grieving the loss of Kwejian, Book flies into the gravitational anomaly to study it, while Culber and Adira give Gray a synthetic body.
Book is numb with grief and haunted by visions of his nephew Leto. Stamets reports that Kwejian was destroyed by an unprecedented gravitational anomaly that must be studied, and Saru returns to Discovery as Burnham's first officer.
With early data ruling out several theories, Book volunteers to pilot his ship into the anomaly, and Burnham reluctantly agrees. He comes back safely, but the anomaly then shifts course and damages Discovery, leaving its path impossible to predict. Afterward Book begins to open up to Burnham. Culber and Adira transfer Gray's consciousness into a synthetic body, using the same technology that was used for Picard. Olatunde Osunsanmi directed.