A gang of London university students graduate from local credit card fraud to a $20 million diamond heist in Miami when they piss off a crime lord and have two weeks to pay him restitution. The preposterous Plastic purports to be based on a true story, but good luck trying to find out what those actual events were. They cannot possibly be the nonsense we see depicted here. Such as when fraudster chief Sam (Ed Speleers: Eragon) easily recruits the gang’s Smurfette, Frankie (Emma Rigby: Endless Love), whose pants he’s trying to get in to and who also just so happens to work for a credit-card processing company. (Sure, a college student in a part-time job would have access to precisely the sort of sensitive information about high spenders that makes an identity thief’s job a snap.) Later, Frankie graduates to damsel in distress when the crime lord (Thomas Kretschmann: Stalingrad) gets extra angry. The heist finale is egregiously implausible, relying as it does on a diamond exec being fooled by the gang in some bad wigs and phony accents into behaving in the stupidest ways possible. The film is probably meant to coast on the alleged charm of the gang — which also includes Will Poulter (We’re the Millers), Alfie Allen (Game of Thrones), and Sebastian De Souza — but they’re a bunch of sociopaths, with Sam the worst of them, and deeply unpleasant to spend time with. The script, by director Julian Gilbey with Will Gilbey and Chris Howard, tries to convince us they’re all merely Robin Hoods stealing from the insurance companies that will cover their crimes for the victims, crimes they’re forced into because there’s no way any of them will ever end up with decent jobs in this lousy economy. But I’m not buying it. Not even with a stolen card whose bill will never get to me.