After a gruesome murder at the local Costco, four suburban guys band together to form a neighborhood watch group. For some, it was an excuse to hang with the dudes, and for Evan (Ben Stiller) it was a group designed to solve the murder and catch the killer. They soon find out they’re in for more than they bargained for, as they discover aliens are planning an invasion and posing as ordinary folks in town.

“The Watch” sets itself up as two things: a suburban dude comedy and a sci-fi alien invasion flick. Unfortunately, it picks the lower forms of these two genres. The comedy portion features everything you’d expect: the authoritarian leader (Ben Stiller), the brash Man’s Man (Vince Vaughn), the awkward, lives-with-his-mom guy (Jonah Hill), and the quirky outsider (Richard Ayoade). With such a fantastically funny cast, you’d hope for a fantastically witty, funny script. But that’s not the case here. Rather than going for clever humor, which all four men can do so well, the script opts for crude vulgarity and an over-emphasis on the phallic. Which translates over into the alien invasion portion, which seems somewhat tacked-on just to give them motivation. Really, the enemy could have been anything. While the aliens did look pretty cool, the threat of their invasion just wasn’t there.

While the failures of the script are quite obvious as the film rolls, the strengths are just as obvious. Stiller and Vaughn are great together on screen, and it’s clear that all four comedians are excellent at improvisation and physical comedy. Vaughn in particular really sells this whole movie. He’s believable as an overly stereotypical yet compassionate blue-collar guy who puts the safety of his daughter well above anything else in his life, even if being a teenager means most of their communication is through yelling. Hill’s weird wannabe cop/militia man is incredibly awkward, though he manages to make the awkward exchanges just barely tolerable. Ayoade was surprisingly well cast, even though the discomfort in saying his unexpectedly vulgar lines is palpable. The only disappointment for me is Will Forte, as he is once again completely wasted on a side character that doesn’t get nearly enough screen time.

In terms of the alien invasion half of “The Watch,” there are no surprises. When the ball starts rolling in the last 30 or so minutes of the film, there is finally a sense of a science fiction story happening. But before that, it’s just a means to an end, not a crucial narrative element. Which really isn’t that much of a surprise, seeing as Seth Rogan wrote the script and his strengths lie more in buddy comedies than science fiction. Why bother using aliens in the first place? The movie spends so much time trying to sell the neighborhood watch group that the aliens don’t really matter. Except for having an excuse to make a giant phallus joke, with a smattering of other phallus jokes along the way.

Yet somehow it still manages to be funny, if only because the actors are trying so hard to make something out of nothing. While the crude dude humor works during the first half, the payoff just isn’t there. If this movie does anything, I hope it kills the current trend of juxtaposing stereotypical white suburban life with rap music for a cheap laugh. “Office Space” got it right, and every use since then is just a lazy way to get the audience to chuckle. And that’s really what “The Watch” is, 100 minutes of cheap laughs.