Verona (Maya Rudolph) and Burt (John Krasinski) are looking for a place to live — and they'd like to find it before she gives birth, which is only three months away. But settling on a home isn't their only concern.

Burt wants to get married; Verona doesn't. She worries that they're not where they should be in their lives; he's fine with the way things are. Her parents are dead; his might as well be.

"Away We Go" is a smart, engaging comedy about making the transition from being a couple to being a family. Working from a screenplay by Dave Eggers (author of the book, "A Heartbreaking Work of Staggering Genius") and Vendela Vida, director Sam Mendes ("American Beauty") balances hilarity with hysteria. It's a freewheeling approach that's new to his work.

The story follows Verona and Burt as they embark on quest that takes them from Colorado to Canada, and from Madison, Wis., to Miami. Along the way, they encounter Burt's oblivious parents Gloria (Catherine O'Hara) and Jerry (Jeff Daniels), Verona's stylish sister Grace (Carmen Ejogo), Burt's flaky childhood friend LN (Maggie Gyllenhaal) and Verona's lewd former boss Lily (Alison Janney).

Rudolph, a veteran of "Saturday Night Live," turns in a performance of such poignancy and depth that an Oscar nomination is virtually guaranteed. Krasinski, of the TV show "The Office," offers a slight variation on his image as lovable Everyman, but that's perfect for the film.

Also excellent are Chris Messina as Tom, a devoted family man, and Paul Schneider as Burt's troubled brother, Courtney.

"Away We Go" plays like a companion piece to Mendes' previous film, "Revolutionary Road" (2008), which was also about a couple going through changes. If the commercially disappointing "Road" was a Rorschach test, "Away" is a carnival ride. And at the box office, that should make all the difference.