When Lorene Scafaria decided to write a movie about the end of the world, she knew she didn't want it to be your average Michael Bay fodder. "I remember going to see Deep Impact and not really feeling that emotional until Téa Leoni and her dad are standing on the beach there," she says, referencing the climactic scene in which Leoni's character reconnects with her father while the apocalypse approaches. "And then I realized 'Oh my God, these are people,' and I was just sort of keeping that in my head."

Having written the screenplay for 2008's Nick and Norah's Infinite Playlist, Scafaria played with the idea of an "infinite" love. "I just thought about putting a cap on that," she says. "If you take forever off the table, what does that do for a love story? It was less of a reaction to end-of-the-world movies and more of a reaction for me to romantic comedies, because it's a genre that I've always loved that's kind of gotten off-track a little bit, or formulaic."

The script Scafaria came up with, Seeking A Friend For the End of the World, certainly puts rom-com formula through considerable revision. The dark comedy chronicles the growing affection between Dodge, an apathetic corporate guy, and Penny, his vivacious young neighbor, in the 21 days left before an asteroid obliterates Earth. Besides her screenwriting credit, the film also marks Scafaria's directorial debut. "I pitched it with me attached to direct," she says. "I didn't really give anyone a choice."

Scafaria's specific vision for the movie included two specific stars, Steve Carell and Keira Knightley, for the lead roles. Fortunately for Scafaria, both actors took to the material immediately. "It's not the viewpoint of the President on the hotline talking to the astronauts," Carell says. "It's just people. It's just the normal rank and file who are dealing with this information." Knightley says she called Scafaria the same day she finished reading the script to sign on to the project. "I'd never read anything like it," Knightley says. "I liked the idea of taking this subject that's sort of as death, doom and destruction as you can possibly get, and then putting this kind of other twist on it."

The film's third major character gets nearly as much screen time as Knightley and Carell, but doesn't even get top billing. A dog named Sorry joins Penny and Dodge on their end-of-days road trip to find Dodge's old high-school sweetheart. Carell has a mouthful for his canine costar. "That dog was just a bastard," Carell says. "He had a huge rider and all sorts of requests." In fact, two dogs took turns playing Sorry in the film, and Carell says they had very different personalities. "Dog number one, it was like he knew where the camera was," Carell says. "It was kind of uncanny. Dog number two was just sort of an A-hole."

Among the non-furry members of the cast are a veritable army of cultish comic talents, including Patton Oswalt, Gillian Jacobs and Rob Corddry, in brief supporting roles. "There's all sorts of great actors in this," Carell says. Scafaria says the cast spent a lot of time talking over the material. "I think everybody came together because they were interested in these themes so much," she says. "Everybody was interested in having these kind of deep conversations and stuff."

So how would the film's stars feel about the end of the world? "I wouldn't want to know about it," Knightley says. "Ignorance is bliss. If anyone said you've got 20 days to go, I'd just be sitting in the corner crying." Carell has a different take. "It makes you think about what you would do and the choices that you would make," he says. "And I'd probably just eat. I'd eat a lot of crap." | RDW