Uptight lawyer Jason Kelly is one week away from marrying his boss's controlling daughter, putting him on the fast track for a partnership at his firm. Right before the wedding, Jason's grandmother dies. His grandfather, Dick, asks Jason to drive him to Florida ostensibly to honor his late wife's wishes to have her ashes scattered there. Despite his reservations about the trip interfering with his wedding preparations, Jason honors his grandfather's request, unaware of Dick's true intentions.

Upon hitting the road, Jason quickly discovers that his grandfather is not the somber widower he expected but instead a foul-mouthed, free-spirited former Army general on a mission to live life to the fullest. Dick drags his grandson into a series of wild escapades, including bar fights, karaoke, and encounters with party-goers, as they head to Daytona during spring break. Through the chaos, the grandfather-grandson duo meet Shadia, an environmental photographer and former classmate of Jason's, sparking an unexpected connection that challenges Jason's perspective on life and love.