When actors craft movie roles for themselves they tend to play to their own ever-active egos. So Matt Damon becomes the hyper-intelligent wunderkind of Good Will Hunting. Ben Stiller transforms into a male model in Zoolander. Vincent Gallo casts Chloe Sevigny to...

It's a surprise, then, that the character closest to Emma Thompson's heart is Nanny McPhee, a snaggletooth wielding, boil encrusted uber-nanny whose brand of cool discipline terrifies and charms in equal measure. 2005's original was scripted by Thompson and based on the Nurse Matilda series of books by Christianna Brand and made an impressive amount of money at the box office.

The sequel diverts from the books inasmuch as the eponymous Nanny doesn't return to the children of the first film but rather finds a new family in need of help, governed by frazzled mother Isabel Green (Maggie Gyllenhaal). We're out of 19th Century England and onto a rural farm during World War 2.

Of course, Mr. Green (Ewan McGregor) is off fighting the war, so it's up to his wife to look after the house and take charge of her kids, Norman, Megsie and Vincent. Things get even more complicated when their spoiled cousins Cyril and Celia come to stay to escape the Blitz.

And with the family's patriarch away, Mr. Green's scheming brother Phil (Rhys Ifans) is free to put pressure on Isabel to sell the farm so he can cover some gambling debts.

The stage is set for the arrival of Nanny McPhee, who'll teach the children five valuable lessons through her curious brand of magic. From there on out it's all hilarity and hijinks, until a MacGuffin gives us an ending.

In a sequel this formulaic, there's not really much to add over a reaction to the first film. The law of diminishing returns mean this isn't quite as fresh or charming as the original, but the rural wartime setting keeps things interesting enough and there's something to the character that makes her inherently watchable.

Thompson clearly relishes the role - it comes through in her performance. Though as we see the Nanny tackle a second family in the same way as the first, and learn that she's touched the lives of many children over an indeterminate lifespan, there's a certain sense that, like the formula of the film, her job is a little too procedural for it to really engage her.



Still, the emotional engagement is really for the kids, led by Asa Butterfield, last glimpsed in a slightly darker wartime tale - The Boy in the Striped Pajamas. They strike that classic balance between bratty and engaging, as so many child actors have demonstrated in family films like this.

But that's part of the problem; it's all a little familiar. We've seen kids like this in Mary Poppins, whose nanny may have been a little more vocal but was still cut from the same cloth as McPhee. We've seen hijinks and scheming in Roald Dahl adaptations. Does Nanny McPhee Returns really add anything the genre?

Indeed, at its weakest this is sub-straight-to-dvd fare, with Rhys Ifans hamming it up beyond belief as the dastardly Uncle Phil. At least he's spared the real indignities forced on Maggie Smith, who plays an absentminded shopkeeper to such embarrassing over exaggeration that it's hard not to cringe whenever she pops up.

Maggie Gyllenhaal struggles as well, straight-jacketed into an English accent she has no business attempting and basing her character on a dictionary-defined form of 'frazzled' which is at best irksome. At its worst it makes one want to reach into the screen and tell her to get over it.

It's tough to figure out whether the film's failings are really enough to warrant a dismissal, though. If any charm at all comes through, there's a good chance family audiences will find it in spades - they're wont to enjoy much less charming works.

Maybe Nanny McPhee Returns isn't the most original of family films, and perhaps its appeal isn't quite as wide as the likes of Harry Potter, with which it shares more than a handful of actors. But it'll just about keep parents entertained as well as kids, and even in a family marketplace as saturated as this, that's a rare bit of magic.