Steve Carell and Keira Knightley, together as a couple who’ve fallen suddenly and madly in love? Surely the apocalypse is nigh.

It’s coming in three weeks, to be exact, in “Seeking a Friend for the End of the World,” the feature directing debut from screenwriter Lorene Scafaria (“Nick & Norah’s Infinite Playlist”).

An asteroid 70 miles (113 kilometers) wide is hurtling toward Earth, ensuring destruction and doom for the entire planet. Scafaria explores how people behave when the rules of polite society are stripped away, a premise that isn’t exactly novel – the world ended just last year, much more artfully, in Lars Von Trier’s “Melancholia” – but one that’s brimming with potential for absurdist, satirical comedy.