Every so often, a movie tailors itself around the particular strengths of a stand-up comedian. Top Five, for example, was a terrific recent example of a movie that only asked Chris Rock to be Chris Rock, and the rest of the movie slowly shimmied into place beyond him. Trainwreck tries to do the same with foul-mouthed comic Amy Schumer, and it succeeds for large chunks of time (mostly during its first hour), until it succumbs to the weaknesses of director Judd Apatow.

Apatow makes comedies that are sporadically hilariously yet notoriously overlong and bloated. Trainwreck is no different, and even though it clocks in at two hours, it feels longer. There’s an inexact science to how a comedy should feel, but when the steady laughter stops, and you start to single out scenes that added nothing, the “length,” more than the actual “run time,” becomes an issue. After a blistering first hour, one that shows incredible restraint, crisp editing and a brisk pace that breaks off joke after joke, Trainwreck throws itself into neutral and coasts. Worse, it stalls. Truthfully, it damn near stops, then has to reestablish its momentum (which it does, thanks to an hilariously self-deprecating dance sequence that reminds you how funny Trainwreck was, before it let a crushing sense of melodrama suffocate all of its fun). The blame should shift to Schumer, who receives the movie’s only screenplay credit. Except, we have seen Apatow do this time and time again, so how could we not single out the repeat offender?

Amy Schumer plays Amy, a character comprised of the strongest bits from the comedian’s stand-up routines and sketch comedy. A loose, single gal from Manhattan, Amy was taught at a young age by her adulterous father (Colin Quinn, hilarious in his scenes) that monogamy isn’t realistic. The lesson stuck, meaning that Amy behaves like a stereotypical “dude,” blasting through sexual partners and avoiding commitment even though a string of sentimental guys try to button her down. Amy’s a shocking character, a blatant middle finger aimed at the idea of how women are “supposed” to act on screen. And it’s refreshing the way she plays against type, and embraces her sexual freedom. The credits actually list four “One-Night Stand Guys,” played by fellow comics like Jim Florentine and Bobby Kelly. Dan Soder plays “Dumpster Guy,” because that’s where he and Amy hook up. You get the idea.

Amy’s worldview starts to shift, however, when – on assignment for the magazine for which she writes – she meets and starts to fall for Aaron (Bill Hader), a straight-laced, borderline boring sports doctor. Amy and Aaron shouldn’t fit together. Actually, the longer Trainwreck extends, I found myself hoping that they wouldn’t get together, because he comes across like a nice guy, and she’s a monster. Alas, this is Hollywood, and even a movie that reverses gender stereotypes and attempts to push the envelope can’t avoid the most basic rom-com clichés in the end.

Before we get there, though, the team of Apatow and Schumer deliver some huge, filthy and fantastically offensive laughs. Schumer’s obviously a brilliant observer of the modern dating scene, and isn’t afraid to wholeheartedly wave her selfish flag when behaving like an egocentric lout. Essentially, she’s an asshole. During a painful breakup scene, Amy tells the heartbroken Steven (pro wrestler John Cena, surprisingly funny) that she can’t continue the conversation because she’s too high, and bored, and not into him anymore. It’s funny, and honest, and sad. That describes a lot of this movie.

Halfway through, though -- after hysterical comics like Dave Atell, Pete Davidson and Keith Robinson get a chance to briefly steal the spotlight -- Trainwreck becomes less of an Amy Schumer movie, and more of a Judd Apatow movie. Remember when This is 40 focused heavily on Paul Rudd and Leslie Mann’s marriage problems, and the movie stopped being fun? That happens here. I don’t necessarily want to give away the issues that Amy runs into, but they drag the film down. At first, it’s intentional. But as Apatow gets more leeway, he includes too many scenes that don’t add to the story, and only disrupt the flow. One is a mock intervention. One’s a lengthy baby shower that only reiterates traits we’ve already been told about Amy a dozen times (she’s crude, she’s selfish, she’s unpredictable… we got it). One’s an uncomfortable encounter with an intern, played by Ezra Miller.

This is what Judd Apatow does, though, so you have to go into Trainwreck knowing that even though he’s working from someone else’s material for the first time, his approach to comedy – which leaves a lot of room for drama – is still filtering the results. If you like Apatow, and enjoy his balance of tragic and comic, you’ll enjoy this. If you prefer unfiltered Amy Schumer, you’ll find more of it on her weekly sketch program.

Sean O'Connell
Managing Editor

Sean O’Connell is a journalist and CinemaBlend’s Managing Editor. He's frequently found on Twitter at @Sean_OConnell. ReelBlend cohost. A movie junkie who's Infatuated with comic-book films. Helped get the Snyder Cut released, then wrote a book about it.