The Battle of the Five Starships

Picard and Data try to figure out who among the crew are imitations. Picard kills Laforge and then decides to steal a new chief engineer from Voyager. But both the Defiant and Archer's new Akira-class ship come to Janeway's help and attack the Enterprise. Even Kirk's Enterprise emerges from a temporal anomaly. The Enterprise D is destroyed but Picard and Data escape on a shuttle and go into the temporal vortex. Voyager also gets pulled into the vortex but emerges in the late 20'th century, while Picard and Data arrive in the 19'th century, where Gul Dukat is secretly conspiring with time-traveling aliens. Picard decides to turn Data into a woman.