'Laggies' Trailer: Keira Knightley Parties With Teens, Tries to Figure Out Future (Video)

The Lynn Shelton dramedy, which premiered at Sundance, co-stars Chloe Grace Moretz and Sam Rockwell.

"Did you hear the one about the grown woman who started hanging out with a bunch of pubescent kids?" Sam Rockwell asks Keira Knightley in the first trailer for the upcoming indie film Laggies.

What sounds like the beginning of a joke is actually a fairly apt description for what happens to Knightley's character in the Lynn Shelton-directed dramedy, which premiered at Sundance.

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Knightley plays Megan, an aimless young woman who attends her 10-year high-school reunion and realizes not much has changed. After her high-school boyfriend proposes to her, she panics and runs into a group of teens, led by Chloe Grace Moretz's Annika, who convince her to buy them beer. After partying with them, she later moves in with Annika's family, claiming she needs "to lay low for a week."

There, she meets Annika's father, Craig, played by Sam Rockwell, who finds it, understandably, odd that she's spending so much time partying with teenagers.

A love connection is sparked between Megan and Craig, but they also confess the challenges they both face adjusting to adulthood.

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In the trailer, Megan is shown counseling Annika, telling her, "You can't keep putting aside what you want for some imaginary future. You just gotta suck it up and go with your gut."

A24 bought Laggies out of Sundance and is planning to release the film, written by Andrea Seigel and co-starring Ellie Kemper and Jeff Garlin, in select theaters on Oct. 24.

Watch the full trailer above, and watch Knightley talk to The Hollywood Reporter about the film at Sundance in the video below.