Kevin Hart is one of those actors/comedians who does well in the sidekick role, but struggles to lead an entire movie. Die Hart makes fun of this dynamic as well as poking fun at Hart's image and acting abilities. Its also the reason the move doesn't quite work, ironically.
Kevin Hart plays...well, Kevin Hart. He becomes upset with the image of himself as a short sidekick who is just there to be the comic relief. He wants to be seen as an action star. When a guerilla tactics director (Jean Reno) offers him an action role, but only if he agrees to attend an rogue action camp, Hart agrees. The camp is run by Ron Wilcox (John Travolta) who is, lets say, slightly mad. The methods Ron uses to teach Kevin to be the hero are both dangerous and outrageous. Soon, a second actor, Jordan (the lovely Nathalie Emmanuelle) joins the camp and becomes Kevin's classmate. Even Josh Hartnett has a cameo as himself, a former graduate of Ron's acting school. Milana Vayntrub (the AT&T spokesperson) has a small role as a talk show host.
The fun in the movie is that Hart really is thought of as just a comedic sidekick. The fact that he is willing to mock his image is both redeeming and funny. There are some genuine laughs in this film, notably the early scene of Hart melting down during an interview on the live morning talk show as well as the outrageous stunts Ron makes him perform. The problem is the gimmick runs out of steam after a while and only Hart's sincerity and energy hold it together. The "secret" revelation of what is really going on is telegraphed a mile ahead, but its still entertaining. Still, this is a decent 84 minutes of insanity that was well worth the time.