Newly engaged, Ben Murphy (John Krasinski) and Sadie Jones (Mandy Moore) can't wait to start their life together and live happily ever after. The problem is that Sadie's family church, St. Augustine's, is run by Reverend Frank (Robin Williams), who won't bless Ben and Sadie's union until they pass his patented, "foolproof" marriage-prep course. Consisting of outrageous classes, outlandish homework assignments and some outright invasion of privacy, Reverend Frank's rigorous curriculum puts Ben and Sadie's relationship to the test. Forget happily ever after--do they even have what it takes to make it to the altar?