Ride Along Kevin Hart, Ice Cube, John Leguizamo. Directed by Tim Story. Rated PG-13. Opens Friday.

Kevin Hart might be better in small doses. His supporting role was the best part of director Tim Story’s otherwise execrable romantic comedy Think Like a Man, but Story’s Ride Along has entirely too much Hart. As aspiring cop Ben, Hart is manic and exhausting, constantly blabbering and bumbling. Ben is stuck spending a day with glowering detective James (Ice Cube), whose sister is Ben’s girlfriend and intended fiancée, and of course Ben finds himself caught in the middle of James’ investigation of a secretive arms dealer. The pair have a typical buddy-cop dynamic, learning to appreciate each other’s strengths over the course of the movie. Hart’s shtick gets tired quickly, and Cube only has one note to play as the humorless straight man. The inconsistent humor takes a backseat to incoherent action in the movie’s sluggish third act, turning Ride Along from a mediocre comedy into a rote thriller with occasional weak jokes.