Jennifer Aniston's fears husband Brad Pitt was attracted to Ocean's Twelve love interest Catherine Zeta-Jones have proved unfounded - they've reportedly got no on-screen chemistry.

The Fight Club hunk reprises his role as sexy conman Rusty Ryan in the George Clooney-starring thriller, and the Chicago Oscar-winner is his sweetheart Isabel Lahiri. But movie bosses have been left scratching their heads after seeing their scenes together, which allegedly fail to set the screen alight.

And producers are particularly confused as the duo have become firm friends off-camera.

A source explains, "They work well together but there's definitely no spark.

"Producers are trying to work out ways of injecting a bit of sizzle into their scenes."