Every married couple has their secrets. But Mr & Mrs Smith's go a little deeper - unbeknown to one another, they're both slick guns-for-hire.

They say - or at least Pat Benatar does - that love is a battlefield so while Mr Smith (Pitt) keeps his arsenal in a vault beneath his garden shed, it's only natural that his wife - being a woman - has hers hidden in the oven.

For six years they've managed to keep their secret lives secure...but one day they're sent on the same hit in the Mexican desert and their marital cover is blown.

With only a lifeless marriage to bind them, they both revert to assassin mode and an unedifying betrayal of their marriage vows as they try to wipe each other out.

"I missed you," Pitt tells his wife over dinner after their head-to-head in the desert. "I miss you too," is her laconic reply.

This slant on the battle of the sexes has the look and feel of Ocean's Eleven with Pitt practically reprising his role as the ice-cool fixer dispensing bon mots as rapidly as bullets.

Jolie shows herself to be a decent comedy actress, sending up her Tomb Raider bird-with-big-bazookas role with aplomb while sparking hotly off Pitt. Ooh er.

The action - replete with Bond-style gadgetry - is dispensed with the usual efficiency but it's the dialogue that provides the real fireworks.

Scriptwriter Simon Kinberg has provided an incendiary device of comedy lines built around Pitt and Jolie's relationship foundering on footings of lies and half-truths.

Jolie used a jobbing actor (which Pitt spotted on Fantasy Island) to act as her father at their sham wedding while Pitt's past is a similar tapestry of deceipt.

The story is bookended by a drily drole session on a Relate-style marriage guidance couch where phrases like you have to give your marriage "your best shot" take on a whole new resonance.

Mr & Mrs Smith make a lovely couple...but you wouldn't want to spill anything on their carpet.

Tim Evans