Rewatching ST:TNG after a 20-year break.
A space anomaly activates an alternate timeline in which the Enterprise-D is a bustling battleship, Picard is a hard-edged militant facing defeat after decades of war against the Klingon Empire, and somehow only Guinan realizes something’s wrong.
This version of Picard struggles with ethical complexities that “our” Picard could resolve after only a few sips of tea, Earl Grey, hot; however, great scenes with Guinan make this extra-crusty Picard intriguing and familiar.
The space thing of the week is an unexplained timey-wimey swirl, but what comes through the swirl is cool — the Enterprise-C, which should have been destroyed 22 years earlier while defending a Klingon outpost against a Romulan attack. In the “correct” timeline, their honorable actions opened the door for peace with the Klingons.
Apart from the teaser in which Guinan introduces Worf to an Earth drink and he actually cracks a joke, this episode is best remembered for the return of Tasha Yar, who with help from Guinan intuits her opportunity to make a meaningful sacrifice.
Captain Garrett, sporting a no-nonsense Janeway-ish bob and attitude, and Lieutenant Castillo, who talks about his mother and crushes adorably on Yar, supply some welcome guest-star texture; however, this is not a backdoor pilot focusing on the visiting characters, so our sense of the the Enterprise-C as a real community of people displaced by time remains sketchy, and the immensity of their sacrifice is muted.
Despite my quibbles, I consider this to be one of the really great episodes of TNG, though that feeling is complicated by my foreknowedge of how the show-runners would fumble an upcoming continuation of the Enterprise-C storyline.