Doug Harris (Josh Gad) is a nice guy with a high-powered job and a gorgeous fiancee, but with only one week to go before his big wedding to his dream girl Gretchen (Kaley Cuoco-Sweeting), he has yet to find his best man. Cue Jimmy Callahan (Hart) the owner of Best Man Inc., which provides a rather unique service for men who need to juice up their weddings: For a fee, Jimmy will be your best man -- and not just any best man, but one whom your guests will be talking about for years to come..