Watched by millions as the lovesick Jim in the US version of 'The Office', John Krasinski has only appeared in supporting film roles until now. Given that he's such a likeable actor, and one with such good comic timing, you'd hope that his first major role on the big screen would be as memorable as his work on the small one. Unfortunately 'Licence to Wed' isn't that movie.

Having gone out together for three years, the easy-going Ben Murphy (Krasinski) finds just about enough focus to propose to the super-organised Sadie Jones (Moore). He wants a wedding in the Bahamas but she wants to be married in her local church. Ben agrees, but that was before he met Reverend Frank (Williams), a man who won't let just anyone walk down his aisle.

Booked solid with weddings for two years, Reverend Frank gives the couple a choice: wait patiently or cram his nine-month pre-marriage course into three weeks and take up the cancellation that's become available. Ben and Sadie choose the latter - now will true love survive?

Here's a riddle: how can a film directed by the man behind nine episodes of the US version of 'The Office' - including the all-time classic 'Casino Night' - starring one of its leading men and with two of his co-stars in that series also appearing onscreen here be such a disappointment? Too short in terms of both minutes and standout gags, 'Licence to Wed' is more of a rush job than Ben and Sadie's wedding.

The set-up is a good one: madly-in-love couple come up against mad reverend and the relationship starts to buckle. Instructed by Reverend Frank that they have to keep their hands off each other for three weeks or he won't marry them, Ben and Sadie also have to contend with excessive punctuality demands, unhinged role playing classes and two robotic babies they must bring everywhere with them - plus their apartment has been bugged. But 'Licence to Wed' never makes full use of the richness of the cast and scenario at its disposal and, robobabies aside, lacks memorable scenes.

Part of the problem here is that Kwapis and the scriptwriters seem unsure whether to keep the film on the family fun side or let rip a la the Farrellys - there really was no choice. There should've been great scenes involving a stag night or hen party; there should've been more for co-stars Christine Taylor, Peter Strauss and Grace Zabriske to do and there should've have been lots more humiliation and one-upmanship involving Krasinski and Williams. Instead there's a movie that seems like it was made specifically with long haul flights in mind.

There's no doubt that Williams is a funnier man than what he has to do here, and shackled with a child actor sidekick, he doesn't get the chance to go truly manic. As for Krasinski and Moore, their characters are interchangeable with countless others - his talents aren't fully exploited and she gets even less to work with.

This isn't the date movie you want to go and see; by all reports that's the Katherine Heigl-starring 'Knocked Up' in two weeks' time.

Harry Guerin