Doug Harris (Josh Gad) is a loveable but socially awkward groom-to-be with a problem: he has no best man. With less than two weeks to go until he marries the girl of his dreams (Kaley Cuoco-Sweeting), Doug is referred to Jimmy Callahan (Kevin Hart), owner and CEO of Best Man, Inc., a company that provides flattering best men for socially challenged guys in need. What ensues is a hilarious wedding charade as they try to pull off the big con, and an unexpected budding bromance between Doug and his fake best man Jimmy.