It's frustrating when the funniest parts of a movie are in the trailer. But in a new twist on an old annoyance, you have to wait until the credits roll to see the really funny stuff from Date Night, which is comprised of outtakes of stars Tina Fey and Steve Carell riffing on each other.

It seemed almost too good to be true, of course, having Tina Fey and Steve Carell costar in a comedy. Fey, known for her biting wit and bon mots, plays Claire, a real estate agent in Jersey; she belongs to a book club, she tries to sell people huge houses with pickled wood floors, and she is emphatically No Longer Sexy or Cool, as we see in the trailer. Carell, who plays her tired but more or less content husband, is talented at playing characters who retain their humanity, vulnerability, and self-awareness in even the most absurd situations (i.e. Little Miss Sunshine, The 40 Year Old Virgin), which comes into play here. In addition to his talent for playing self-important putzes as in The Office, he's also an underrated dramatic actor, as in Dan in Real Life. They both serve these talents up, but with wildly uneven results.

Together, you'd think they would be a powerhouse of funny, of self-aware awkwardness and intelligence, of finding the sweet spot between harried marrieds and two people caught in a totally off-the-wall night in the big city. We get tantalizing glimpses of what could have been, given better writing, editing, and direction. (Director Shaun Levy's resume includes two Night at the Museum films, The Pink Panther, and Just Married, while writer Josh Klausner has Shrek the Third under his belt.)

Phil and Claire Foster are a likeable, smart couple who seem to love each other a great deal. They're tired, sure, and they don't have the best sex life any more, although even Phil's frustration seems almost good-natured. They even have a weekly date night with a baby sitter, but somehow we're supposed to even scorn this attempt at reconnecting - they always go to the same restaurant and order the same things and supposedly talk about the same old thing, but their dinner scenes are actually some of the best in the movie. Intimate and funny, they play a game where they try and guess what the story is with the other diners. It's sweet; they are reconnecting to the parts of themselves who don't recommend Roth IRAs to young dumb couples or show fussy couples countless houses.

But one night during their weekly book club, Haley (Kristen Wiig) tells Claire that she's leaving her husband, that it was the best decision she ever made, and that she wants to go out and experience sex with three men, among other things ("I have stress dreams about that!" says the disbelieving Claire). In the other room, her husband, played by Mark Ruffalo, tells Phil he realized they were just "really excellent roommates." This inadvertently kicks off the Fosters' big adventure in New York City. Fey, whose stock-in-trade is how normal she looks (relative to, say, Angelina Jolie?), dresses up, and Phil takes her to a fancy restaurant in the city, where they steal someone's reservation and a totally abysmal mistaken identity plot takes over.

Corrupt cops, car chases, and weird cameos are now the name of the game. Mark Wahlberg, channeling his Calvin Klein underwear model days, is a most unlikely former special ops dude who was once a client of Claire's. He's sort of a shirtless Ubermensch, there to make Phil and all other men feel inferior with his crazy technology gadgets, sexy Israeli girlfriend, and scads of cars. Claire and he enjoy a slight flirtation, while Phil plays the "dorky husband," as he complains later in an equally unlikely heart-to-heart with Claire in the middle of a car chase. And Claire responds with a typical harried wife/mom outburst about being overworked, exhausted, etc. etc. All true things, no doubt, but the words coming out of this woman's mouth - not even Fey's mouth, but Claire's mouth - are so canned that it's impossible to take seriously.

And that's the problem with Date Night. In addition to the limp After Hours vibe that many reviewers are mentioning, Phil and Claire are wedged into an unsatisfied married couple stereotype that isn't really held up by the overall dynamic of their relationship. The stale writing never really gives us a full picture of Phil and Claire, and what we do see is strictly by virtue of Fey and Carell's improv abilities and natural likeability and intelligence. Unfortunately, every time they start to take the audience there, the plot takes over and we're left dangling. This is, no doubt, a problem with writing and direction, but also with poor editing that shows the characters in different positions without any real explanation. For instance, during their car argument slash open heart, Carell is shown from the side when he talks, and when Fey responds, he's facing forwards. What was cut out? Something, I don't know, funny or a more honest discussion about feeling like an unappreciated husband and a tired wife who works all day to come home and cook dinner and fall into bed?

Claire is alternately eager to please in a way that rings totally false - "Do you like this? It's the only one that covered up my C-section scars!" she says eagerly about a borrowed corset in one of the more ridiculous scenes - only to switches gears to take charge of a situation getting out of control or keep her husband from totally freaking out. As I mentioned, the best scenes are when they make fun of other diners in their game of "What's their story?" It shows their natural chemistry and their goofy wit that's mostly hidden throughout the movie. "That's really interesting, but I have go to home and fart in a box," she says in a nasal imitation what they guess is a girl on a first date with a guy who won't stop talking.

For some reason, the things that Fey and Carell normally do in movies or on TV - such a scene featuring them gyrating awkwardly on a platform with a stripper pole in the middle - is so much more embarrassing to watch here in Date Night. I just can't imagine what they were thinking when they read the script and signed on. Maybe that they could save it through sheer willpower.