A light and easily digestible genre treat, “Free Fire” is pure cinematic joy. At a scant eighty minutes the film is succinct (throwing us into its nutty and ultraviolent scenario) and freewheeling — fueled by snappy comedic dialogue, bullets and gore. Directed by rising British auteur Ben Wheatly, (“Kill List” “High Rise”) “Free Fire” giddily illustrates how easy it is for a seemingly stress free underworld deal to go terribly wrong. How exactly? Just throw ten testy, aggressive gangsters with fragile egos into an abandoned warehouse (circa 1978) and watch as chaos ensues over the course of a single night.

At the beginning of the night, two gangs arrive at an old Boston warehouse for a gun deal. They make small talk with one another, the usual tough guy ribbing for the most part. It’s nothing too serious, yet. But during the next ten minutes Wheatly shows how little things like petty insults can eventually snowball into something bigger. Other issues arise; the gang selling the guns brought the wrong type and personal vendettas between rival gang members find their way into the mix. The water quickly boils over and before long the first shot has been fired and the two gangs find themselves in a gunfight.

But even that doesn’t go as smoothly as it should. Instead of being a nonstop barrage of bullets and mayhem the gun battle is slow and clumsy, happening in fits and spurts. From time to time, they even forget why they’re fighting in the first place. The gangsters trade shots at one another—both gunshots and more petty insults. There’s an awful lot of bickering and joke making throughout but that’s what makes “Free Fire” so entertaining. Wheatly’s script (co written with Amy Jump) is full of delightful rapid-fire banter and one liners (“I’m not dead, I’m just regrouping”). It’s not enough for these impulsive, thin-skinned gangsters to shoot one another, they have to insult one other first. Wheatly seamlessly blends comedy with violence, violence that gets increasingly gory as the night goes on.

Wheatly assembles an impressive ensemble cast, including Cillian Murphy, Armie Hammer, Brie Larson and Sharlto Copley among others, who all deliver delectable scenery-chewing performances. Copley as an eccentric South African gangster, Hammer as the suave bushy bearded liaison between the two gangs and Larson as the token female and craftiest criminal of the bunch are the standouts.

And well, that’s pretty much it. “Free Fire” doesn’t have a lot of depth to it. The characters, while fun, remain fairly two-dimensional and I wish Wheatly would have established the setting/atmosphere a little more. There’s no real substantial reason why the action is set in the 70’s. Additionally, the film isn’t nearly as weird or as ambitious as some of Wheatly’s previous pictures. “Kill List” and its genius blend of mundane crime thriller and “The Wicker Man” remains his best work. Never the less, “Free Fire” is still a violent and funny good time.