Star Trek: 15 Greatest Ever Time Travel Episodes

Perhaps I'm a little biased, but any episode based on the Defiant - the tough little ship that could - is a winner in my book. Combining that little gem with time travel was always going to score added points.

Children Of Time is a pretty conventional story model for Star Trek, using science fiction to frame a moral dilemma (a theme that you will have spotted in a significant number of the episodes on this list). In this case, the Defiant is sucked into the future and encounters a planet of 8,000 of the crew's descendants (and presumably a VERY thin gene pool). It transpires that returning to the past will result in the death of Major Kira in the crash that stranded them on the planet and led to the existence of their descendants.

Again, it's a Sophie's Choice of an episode - albeit loaded with more personal links - and it ends with one of the biggest Holy Sh*t moments in any Star Trek episode as Kira accepts her fate, only to find out that future Odo defied them and altered the flight plan to save Kira and kill off the future generations because he loved her. A nice gesture, obviously, but not only would it burden Kira with the guilt of effectively 8000 deaths, but it would also make their present timeline interactions horribly, horribly awkward.