Star Trek: 10 MORE Greatest Time Travel Episodes

4. Little Green Men

Few words stir the imagination quite like 'Roswell'. Combine that with time travel, the Ferengi, and certainly no weather balloon, you already have a great episode from the start. The rest, as they say, is hyu-mon history.

The chances of anything coming from Mars are a million to one, but the odds are a lot higher for the three — soon four — stooges from Deep Space 9. Joke's on Earth, however, as 1940s (and '50s) America (not Australia) is lambasted to within an inch of its irradiated life. In-jokes also abound from the very beginning. The title, 'Little Green Men,' is a reference to a line from another Trek time travel episode, Tomorrow is Yesterday. "All I ask is a tall ship…" is several references unto itself, and the "contraband to fill it [Quark's Treasure]" is kemocite.

Quark is forever Quark, no matter the time period. Nog is the Starfleet 'straight man,' but still very much a Ferengi out for oo-mox. Rom's newfound genius is both great character development and the conceit. Like for Past Tense, the cause of time travel makes as much sense as it needs to, and that PADD is foreshadowing. Like all the best comedy, Little Green Men only ever takes itself seriously enough not to be taken too seriously.