Jason Kelly (Zac Efron), an uptight lawyer headed down the wrong path, is tricked by his rambunctious Grandpa, Dick (Robert De Niro), into taking an outrageous road trip. While his methods may be unconventional, Dick is determined to teach him how to live life on his own terms.
Jason Kelly is one week away from marrying his boss's uber-controlling daughter, putting him on the fast track for a partnership at the law firm. However, when the straight-laced Jason is tricked into driving his foul-mouthed grandfather, Dick , to Daytona for spring break, his pending nuptials are suddenly in jeopardy.
Between riotous frat parties, bar fights, and an epic night of karaoke, Dick is on a quest to live his life to the fullest and bring Jason along for the ride. Ultimately, on the wildest journey of their lives, "dirty" Grandpa and his uptight grandson discover they can learn from one another and form the bond they never had.