Jillian Bell breaks out in whip-smart comedy Brittany Runs a Marathon: Sundance review

Brittany is exactly the kind of fun big girls are supposed to be; she’s always ready for the next drink and the next joke and she never asks for too much. But what if she did? Brittany Runs a Marathon is the answer: a whip-smart comedy that manages to deliver genuinely funny uplift without ever swerving away from its own dark side.

Jillian Bell (Workaholics, Eastbound & Down) stars as a New York party girl who gets a harsh awakening from her GP when he tells her during a routine checkup that her body mass index is way too high, and her liver is essentially turning into paté. (“Okay I feel like you totally missed the point of those Dove ads,” she replies peevishly.)

The truth is, she’s tired of being the fat best friend — the girl who pivots to silly accents every time the moment gets too real, barely makes the rent with her off-off-Broadway theater job, and hasn’t had actual reciprocal sex in over four years.

So she finds an old sports bra and a pair of sneakers, and pledges to make it to the end of the block outside her Queens apartment. It doesn’t go well. But as she keeps going, and finds an unlikely pair of running buddies — Michaela Watkins’ wealthy, chirpy divorcée and Micah Stock’s sardonic gay dad — her life and her body slowly begin to take a new shape.

Writer-director Paul Downs Colaizzo based his big-screen debut on his own real-life best friend, and there’s a huge amount of affection for both her and his lead actress apparent in the way he lets her story unfold onscreen in all its facets. But he’s tough on her too, whether Brittany is bickering with the happily oblivious slacker she shares housesitting duties with (Pitch Perfect’s Utkarsh Ambudkar) or putting off her well-intentioned brother-in-law (Lil Rel Howery).

The thing that truly makes the movie, though, is Bell. An actress who’s consistently stolen scenes from her more famous costars in projects like 22 Jump Street and Office Christmas Party, she brings a real, messy humanity to Brittany that comedies hardly ever allow a lead character — let alone a non-impossibly-bodied female — to have.

She’s fantastic at one-liners, yes, but also hurt and angry and insecure, sometimes to the point of extreme self-sabotage; losing weight or meeting a guy who actually wants to be nice to her doesn’t fix her problems onscreen, just like it’s not a magic wand in the real world.

Calaizzo does give his heroine a certain kind of happy ending, one that’s satisfying and cinematic in all the ways a good rom-com should be. It feels earned, though, and still open-ended; a sweet victory lap for a race she’ll have to keep running long after the credits roll. A–

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