Good heist movies are rare. This isn't one; it is more modest than good, but there are good things in it.

In 1960, Laura Quinn (Demi Moore) is a smart, professional manager at LonDi, a London firm which is a large holder of world-trade diamonds. She is a master manipulator, although has been slapped up firmly against the glass ceiling for three years. Her recent coup was getting her employers out of hot water from the Russian diamond trade. The only caveat of the deal was that only senior executives should know about it. Rather than finally promote her, the plan is to fire her after the deal goes through.

Hobbs (Michael Caine) has been a cleaner at LonDi for 15 years, and has overheard enough conversations to offer advice to Quinn. The pair make a clear case of overlooked people - no one pays attention to the cleaner or a woman. Upon speculative lunches with friends in high places, she learns no other firm will touch her with a bargepole. Once Quinn realises her fate, Hobbs suggests a plan for both of them to get enough deserved severance pay for both of them - a thermos flask full of diamonds. His tragic motives are kept a closely guarded secret.

Flawless sports a thoroughly decent cast - Michael Caine is wonderfully classy as the ambiguous and charming Hobbs. Moore is better than she's been in a very long time, and Lambert Wilson is equally sharp as an internal investigator. The film boasts at least one lovely switcheroo plot twist. It's also lensed particularly well, with a groovy Sixties atmosphere. And director Michael Radford keeps a clear, if not terribly fast pace.

If ever a film title failed to describe its content, this is it. First of the flaws in Flawless is a terribly dull and sugar-overdosed framing device, with Moore sporting horribly unconvincing age makeup - you've seen better on Doctor Who. There's not much excitement in the film, not least due to the implausible heist plan, which fails to generate much mystery or suspense. Furthermore, in spite of their good seperate performances, the movie doesn't convince about the connection betweeen Quinn and Hobbs, which is what would elevate this beyond other old-fashioned heist thrillers. At least they wouldn't have soporific and languid asides about the gem trade or the sexual politics of the era.