Bewitched

There's magic in the air and it's sprinkled liberally over the first 50 minutes of Bewitched.

Nora Ephron and her sister, Delia, who co-wrote the screenplay, conjure up a delightful, post-modern wheeze, which pokes affectionate fun at Sixties sitcoms, subplots take tantalising shape and characters trade snappy one-liners with a twinkle in their eye.

But then something happens - in two cute wiggles of a witch's nose (and the casting of a nifty rewind spell), the entire mood of the film changes.

Sharp dialogue becomes inexplicably dull, colourful supporting players are sidelined and we're left with a lightweight and predictable battle of the sexes which seems to belong to a different film entirely.

Once Nora and Delia have pulled the proverbial rabbit out of the hat during those first 50 minutes, all that remains is, well, old hat.

Good-natured witch Isabel (Kidman) is fed up with living a charmed existence. So she moves to a cosy little house in sunny San Fernando Valley, California, where she plans to disavow her supernatural powers and follow destiny wherever it might take her.

Fate leads her into the path of comeback actor Jack Wyatt (Ferrell), who is pitching himself as the perfect choice to play Darrin in an updated version of Bewitched.

Isabel is smitten - Jack seems to be the embodiment of a mortal, quite unlike the dashing warlocks she is used to dating.

He is equally enamoured - she has a cute button nose which bears a startling resemblance to the nose of Elizabeth Montgomery who originally played Samantha.

With this in mind, Jack resolves to persuade Isabel to play Samantha to his Darrin. It's a match made in heaven, or so they think.

Love is also in the air for Isabel's father Nigel (Caine) as he makes amorous advances to actress Iris Smythson (MacLaine), who is playing Endora in the show. But she harbours a dark secret too.

Kidman plays Isabel with a breathless Marilyn Monroe voice and just the right amount of naivity to convince us she would indeed fall madly in love with someone as pompous and selfish as Jack.

The Oscar-winning actress has to work hard for her laughs but you have to admire her determination in the face of adversity - aka Ferrell, who has been given carte blanche to gurn and mug.

MacLaine and Caine exude an easygoing confidence their co-stars would do well to mimic, contrasting with Chenoweth's hilariously hyperactive turn as Isabel's effervescent neighbour.

The wonderful in-jokery of the first half makes the dreary second hour slightly easier to bear.

Bewitched casts a heady spell - unfortunately the effects wear off before you even leave the cinema.