Tony Gilroy has spent most of his time in the film industry writing scripts (The Devil's Advocate, Proof of Life, the Jason Bourne trilogy), and Duplicity is only the second movie he has both written and directed, after Michael Clayton from 2007. Surprisingly enough, the script seems to be the weakest point of the movie, making the plot a bit too complicated. An overkill of nothing-is-what-it-seems plot twists can really be tiring. Thankfully, two A-list actors and a few excellent supporting roles make up for that.

Moviegoers recently saw Clive Owen (King Arthur, Closer) in the thriller The International where he starred as a fearless Interpol agent uncovering the global criminal machinations of financial institutions. This time, he is Ray Koval, a former MI6 agent.

Having quit working for Her Britannic Majesty's Secret Service, Koval lands a lucrative job with a big corporation where his skills are a perfect fit: his new responsibilities include stealing secrets from the competition.

Unlike Owen, Julia Roberts (Pretty Woman, Erin Brokovich) has not been very busy in the past couple of years. She appeared in a few roles with little significance to her acting career and lent her voice to a spider (Charlotte's Web) and an ant (The Ant Bully). Her last truly memorable appearance was as Tess Ocean in Ocean's Twelve, mainly because she played none other than... Julia Roberts. Now she is back as Claire Stenwick, an ex-CIA agent who, like Koval, is on the payroll in a big corporation, except that her job is to protect corporate secrets.

Koval and Stenwick have been long having an affair, but their new jobs are starting to come between them. Things get even worse when their employers, Richard Garsik (Paul Giamatti-Sideways, The Illusionist, the John Adams series) and Howard Tully (Tom Wilkinson-Batman Begins, Valkyrie, In the Bedroom) give them assignments on the opposite sides of the barricade. The bosses of the two rival corporations hate each other like the plague, and in the opening scene, they are ready to jump at each other's throats, dressed in their designer suits and standing next to their private jets, which are identical except for the different corporate logos.

In the meantime, the couple of spy lovers concoct a scheme to steal the formula of a new hit product, worth $40 million. This is the heist of their lives, affording them a much deserved, if somewhat early, retirement and champagne in lavish settings until the end of their lives. The problem is, can they really trust each other?

Of the two stars, Owen feels much more at home as a spy, especially one with the manners of a British gentleman. Roberts is a bit of a letdown, and as for the chemistry between the two actors, viewers just have to take it for granted in the absence of onscreen evidence. Giamatti and Wilkinson are much better in their roles.

Still, Duplicity does not pretend to be a cinematic masterpiece. It is meant to be nothing more than a piece of harmless, unassuming fun, and that's exactly what it delivers. The characters plot a lot, travel a lot, visit exotic places, and dodge perils even if everyone can see what is coming at the end.