Though science fiction makes for a fair share of seriousness and technobabble, it's often at its best with a few laughs mixed in—and a sci-fi comedy that hits on all cylinders is a wonder to behold.
When genre-busting is done right, it can bring out the best of both genres. Plus, funny is funny—be it wrapped in a period drama or the zombie apocalypse.
So, with the alien-hunting genre mashup The Watch opening this weekend, here are some classic sci-fi funny scenes to get you in the mood to laugh.
Paul - "It's Probing Time" scene
When you combine the ideas of Simon Pegg, Nick Frost, Seth Rogen and an alien—you know you're in for a good time. This scene was one of the funniest, with the alien using one of his most famous clichés to scare off a bunch of hillbillies.
Shaun of the Dead - "Use what you have to kill zombies" scene
If the zombie apocalypse really did happen, not everyone would have the right weapons on hand to take them out. This great scene shows what most of us would probably try.
Spaceballs - "Playing with your dolls" scene
In this sci-fi comedy classic, Darth Vader stand-in Dark Helmet spends his alone time in a very odd way.
Army of Darkness - Bruce Campbell beat up by skeletons
The title pretty much sums up this classic scene, which is one of about a million that made Army of Darkness a cult classic.
Men In Black 2 - "Does that come standard?" scene
Wacky gadgets are used to their funniest effect in this scene, where the MiB car shows off its disappearing driver feature.
Zombieland - "Bill Murray's death" scene
One of the greatest things about this zombie comedy was the awesome cameo of Bill Murray, who met an abrupt (and hilarious) end.
Galaxy Quest - "And it exploded" scene
This hilarious, Star Trek-ish parody film was full of great scenes. But the time Tim Allen served as a guinea pig for the transporter was one of the best.
Spaceballs - Michael Winslow's scene
The sound-effect guru gives Dark Helmet a hard time, which is a hilarious exercise in ridiculousness.
Mars Attacks - "Don't run, we are your friends" scene
Though the big-headed Martians claim they come in peace, the huge ray guns they're shooting tell otherwise.
Evolution - "Take the leg!" scene
This commercially meh sci-fi flick developed a pretty devoted fan base, and when an alien creature gets in one character's suit, he's happy to sacrifice his leg to save a few other body parts.
Coneheads - "The splash-less dive" scene
This early-1990s sci-fi comedy was a ridiculous good time, and the conehead aliens' anatomy was especially useful for their teenage daughter on the dive team.
Paul - "The First Encounter" scene
This first alien encounter is definitely not what you'd expect for humanity's first contact with extraterrestrial life.
Men in Black - "Baby squid birth scene"
It's hard to believe we're three films deep into the Men in Black franchise, but the first installment was arguably the funniest. Will Smith gets a quick introduction to the world of alien life while helping birth a gooey squid baby.
Galaxy Quest - When Sigourney Weaver freaks completely out
This flick was full of great scenes, and the moment Sigourney Weaver's character realizes there are real life-and-death stakes, she flips out. And it's hilarious.
Ghostbusters - "Dick-less scene"
This sci-fi classic is full of great moments, but this little zinger was one of the true laugh-out-loud ones.