The only two-part episode of Star Trek: The Original Series created a Star Trek trope that's been used in some of the franchise's best episodes. TOS season 1, episodes 15 and 16, "The Menagerie ...

But now, three quarters through season two of Star Trek: Picard, I'm mad as hell as, simply put, I feel the show has derailed epically, managing to boldly go nowhere for the last 6 episodes.

Descent Part 2 picks up with Dr Crusher ... It was a clear statement in the series' final season's premiere episode - something that carried on into Star Trek: Picard years later.

Now that Picard’s second season is diving into that well too, io9 takes a look back at some of the franchise’s best uses of it, and how time travel lets Star Trek shine. Get the best tech ...