Freeman promotes Mariner to push her off the ship, but the two must work together when xenoforming material from a towed generation ship engulfs the Cerritos.
The Cerritos and the USS Merced tow a derelict generation ship whose cargo includes xenoforming material that can turn inert matter into living matter. Freeman tries to drive Mariner to transfer by giving her the worst jobs, and when Mariner makes them fun she promotes her to lieutenant, hoping the responsibility will push her away.
The material escapes, disables the Merced and starts transforming the Cerritos, and mother and daughter end up cooperating to stop it and rescue the Merced's crew. Mariner is demoted again for mocking an admiral. In the subplot, Tendi accidentally interrupts Lieutenant O'Connor's attempt at spiritual ascension, and his efforts to save her later trigger a painful ascension of his own.