As the smarmy and brash host of a TV finance show, George Clooney joins forces with Julia Roberts, who plays his producer, in a thriller directed by fellow Hollywood heavyweight Jodie Foster.

Clooney peddles stock market tips to the masses with brazen razzamatazz, but one of his hot tips plummets in value, prompting desperate blue-collar investor Jack O’Connell to burst into the studio and take him hostage live on air.

As the ensuing crisis plays out in real time, Foster hikes up the tension. The volatile O’Connell shoots out TV monitors, Clooney is forced to don an explosive vest and SWAT snipers get into position, trigger-fingers itching. The show’s audience, growing by the minute, is hooked. So, up to a point, are we.

Yet given the high stakes, the film isn’t as gripping as it might have been. Dominic West’s slick boss of the hi-tech company behind the slump is too easily fingered as the villain of the piece, which lets Clooney’s pundit off the hook and blunts the film’s message. Still, it is certainly entertaining viewing and very well performed.