On their way back from a medical conference, Jake and Dr. Bashir are diverted to the Federation colony on Ajilon Prime who have been attacked by the Klingons. However, when the the Klingons renew their attacks on the colony, Jake is forced to confront the hard realities of war as battle erupts around him.

When Temporal Investigations arrives on DS9, Sisko recounts how he and the crew of the Defiant traveled back in time to prevent the assassination of Captain James T. Kirk during the original Enterprise's mission to Space Station K-7.