Credit: Alberto E. Rodriguez/Getty Images

What happens when it’s the end of the world as we know it and you don’t feel fine?

Keira Knightley and Steve Carell find out today as production begins on their “pre-apocalyptic” romantic-comedy Seeking a Friend For the End of the World, one of Hollywood’s more unusual approaches to the well-trod disaster epic genre.

Knightley plays Penny and Carell stars as Dodge, two lonely hearts who find they don’t have time to procrastinate anymore in the search for romance. While the movies have ended the world many times over, rarely has that concept been used to tell a love story. “And it’s funny,” James Schamus, CEO of Focus Features, tells EW. “It’s one of the most audacious conceits.”

Here is the world-killing scenario that drives them together:

Seeking a Friend, directed by Lorene Scafaria (Nick and Norah’s Infinite Playlist), is shooting around Los Angeles with plans for release in 2012 (unless that Mayan prophecy turns out to be true, of course).

Credit: Lewis Jacobs/NBC

While the 26-year-old Knightley and the 48-year-old Carell might seem like an odd couple, that’s the point. There’s a lot of humor in hopelessness. And no time to be picky. “It opens with the news report that the laser ray we sent into outer space to try to knock out this meteor shower just didn’t work and so the meteors are coming in a few days. That’s it,” Schamus says. “End of report.”

With no possibility of survival, the other denizens of the doomed world have a choice, Schamus says: “Time to go home now, or: Let’s party.” The cast includes Melanie Lynskey (Up in the Air), Patton Oswalt (Ratatouille), Rob Corddry (Hot Tub Time Machine), and William Petersen (TV’s CSI.)

Carell and Knightley’s characters are “two people who live more life in those few days, and really get the hope they hadn’t had in their lives before, because they weren’t fully living them,” Schamus says. “Once that sense of mortality really does enter into it, they find they’re given the space to be who they are.”

Well, at least temporarily.

Follow EW’s Anthony Breznican on Twitter @Breznican.