Clone-captain William Boimler leads a mixed crew hunting interdimensional rifts.
William Boimler, Brad's transporter duplicate, captains the starship Anaximander on a mission to find the source of the interdimensional rifts threatening the multiverse. His crew includes alternate versions of characters from other Star Trek series, an engineer version of Mariner and several Harry Kims.
Mariner devises a way to track the vessel causing the rifts, which is commanded by an alternate Lily Sloane who invented interdimensional travel instead of warp drive, never realizing it was tearing reality. She agrees to help, but the one Harry Kim who made lieutenant hijacks her ship. The damaged ship explodes in a rift and unleashes an energy wave, and William steers it toward his own universe, trusting the Cerritos crew to find a solution.