Directed by Doug Liman. Starring Naomi Watts, Sean Penn, Bruce McGill, Sam Shepard 12A cert, gen release, 106 min

An outrageous spy scandal in the Bush White House is the basis for this interesting if underwhelming thriller from the director of The Bourne Identity, writes DONALD CLARKE

THOUGH PAUL Greengrass, director of the second and third Bournefilms, made that trilogy his own, we should remember that Doug Liman – a film-maker for whom the word "erratic" might have been coined – set the wheels in motion with his nicely jarring The Bourne Identity. Is this what clandestine operatives really get up to? Are their days truly devoted to strangling Germans and driving inexpensive motorcars off bridges?

Liman seeks to answer those questions with this curious, intermittently successful take on the Valerie Plame scandal. As we suspected, CIA personnel spend, it seems, as much time driving kids to school and bickering over the dinner table as the rest of us.

Decently read American viewers will already have a fair grounding in the facts. The story was less well covered on this side of the Atlantic, so a brief précisis probably in order. In 2002, Plame, a middle-ranking spy (played here by glacial Naomi Watts), found herself investigating the proliferation of nuclear and biological weapons. That job gained added resonance when, prior to the Iraq War, she began probing rumours that Saddam's regime was developing weapons of mass destruction.

Plame’s eventual conclusion was, of course, that no such programmes existed. However, eager to push

the case for war, her superiors – notably the subsequently disgraced Scooter Libby, then advisor to Dick Cheney – overrode her conclusion and continued to argue that Iraq was knee-deep in H-bombs.

Plame toed the line, but her husband, former diplomat Joseph Wilson (Sean Penn), was not so easily silenced. Following a fact- finding trip to Niger, Wilson wrote an article explaining that, contrary to opinions expressed by the intelligence community, that country was not conspiring with Saddam to produce WMDs.

Here’s where things got properly dirty. In an unprecedented move, a US State Department source leaked the information that Wilson’s wife was a spook. Got that?

One suspects that Liman and his British screenwriters, Jez and John-Henry Butterworth, had notions of creating a contemporary All The President's Men. Sure enough, Fair Gamedoes feature a fair amount of muttering in corridors and no little whispering on the telephone. But the stakes never seem high enough – the story is only a story because of that unusual leak – and the conspiracies never feel sufficiently twisty.

Aside from anything else, subsequent studies of Watergate and more recent reports on the CIA’s incompetence prior to September 11th have confirmed that the US intelligence community, despite the film’s paranoid tone, features more fools than knaves in its upper reaches. One can never quite believe that Wilson and Plame are in any serious danger.

Still, as a study of professionals under pressure, Liman’s film works pretty well.

The casting of Penn as Wilson is particularly inspired. Few other actors are so capable of conveying pomposity, self-righteousness and pious indignation. The script is largely generous to Wilson, but (whether consciously or not) Penn’s performance wraps interesting waves of ambiguity about the character. One can’t help but think that this version of Wilson envies his wife’s influential position.

Watts is, perhaps, a tiny bit too sleek and glamorous for her role. But that characteristic fragility helps press home the pressure Plame’s unwanted notoriety brought. Labelled a traitor by the sort of maniacs who scream anonymously down telephones, Watts’s Plame emerges as an intelligent woman who, unlike her husband, only wanted to do her job in peace.

Fair Gameremains, however, something of a problem picture. Not quite a thriller, not quite a domestic drama, it never entirely succeeds in justifying its own importance. Even the most mature adults may, during one of many lulls, find themselves yearning for a bit of Bourne mayhem.