Sometimes, an encounter with a truly annoying seatmate on a train can prove fateful. That's the case for Nancy (Lake Bell, rocking a British accent) in the delightful new romantic comedy Man Up, which opens in New York and L.A. on November 13 and expands to additional theaters and On Demand November 20.

In an exclusive clip debuting on Refinery29, Nancy is headed to London after a disastrous setup at an engagement party. Wielding a sandwich, she winds up plopping down across from an all-too-cheery woman, Jessica (Ophelia Lovibond). Jessica decides to interject after she overhears Nancy's woes, and suggests that Nancy read a self-help tome, Six Billion People and You. Jessica has placed a lot of faith in this book: it's how the blind date she's headed to meet will recognize her. Nancy is having none of Jessica's optimism, nor any of her love for The Da Vinci Code.

But Jessica's passive-aggressive altruism comes back to bite her in the ass after she leaves the book on the train for Nancy. Because Nancy is holding the book in the right place at the right time, Jessica's date, Jack (Simon Pegg), assumes Nancy's the woman he's supposed to meet. Instead of telling Jack he has the wrong person, Nancy, charmed by a Silence of the Lambs reference, just decides to keep up the ruse.

Writer Tess Morris hit upon this scenario after she, like Nancy, was stopped by a man in Waterloo station looking for his blind date. Morris did not find true love out of the incident, but she did find a good meet cute. "I was looking for that hook for two people to actually go on a blind date, which is very difficult in the modern world," she told us. "You can Google people."

Even though Morris did not choose to steal someone else's date, she says that the movie has some "autobiographical" elements. "I don’t really feel embarrassed saying that, because we’ve all had terrible dates and we’ve all found ourselves thinking, How can I actually meet somebody?" she said.

Casting Bell was a "dream scenario," according to Morris. Bell, however, is American, unlike the other lead actors in the film. That wasn't an issue, though. "She did stay in the British accent through the whole of filming," Morris said. "At the end of the shoot, when we were wrapping, she suddenly did her thank you speech in American, and loads of the crew were like, What? She’s not British!"

Watch an exclusive clip from Man Up, below.