"Take a lap - lose the asthma," is the caring advice of smalltown PE teacher Jasper Woodcock (Thornton).

He's the gym instructor who's happy to assume he's running a military boot camp for the puffing, wheezing pupils of Forest Meadow Middle School.

However, his vicious regime propels intimidated fat kid John Farley (William Scott) into pursuing a phenomenally successful career as a motivational speaker and self-help guru.

Fast-forward ten years and John interrupts a book tour to return to his home town only to discover the hated Mr Woodcock is courting his mother (Sarandon).

This time - or so he feels - he's ready to confront Woodcock's vile concentration on every child's weakness while also rescuing mom from a life with his reviled nemesis.

Thornton has recently made a bit of a speciality of off-beam authority characters (Bad News Bears, School for Scandal) but here he really nails it.

His Woodcock is an exquisitely vile creation - a vindictive monster just about made palatable by a sheen of authority yet immune to any easy fixes like third reel redemption.

William Scott shows he's a comedy player of some subtlety while Sarandon evidently revels in the role of sex kitten just - and I mean just - the wrong side of forty.

It's a solid, well-written outing distinguished by the laidback insolence of Thorton's school bully.

Tim Evans