"Marriage is like a phone call late at night," Robert De Niro says, in dulcet voice-over mode, at the outset of "The Big Wedding." "First comes the ring, and then you wake up." Rim shot, please.

A long-divorced couple (Robert DeNiro, Diane Keaton) pretend to be married to help out their adopted son when his biological mother, a staunch Catholic, attends his wedding. No one quite embarrasses ...