(M) **

Director: Jake Kasdan.

Cast: Cameron Diaz, Justin Timberlake, Jason Segel, Lucy Punch, Phyllis Smith, John Michael Higgins.

THIS is too easy, but I'm going to do it anyway: Bad Teacher? Bad movie.

While not a total waste of time, this black comedy is big on the dark but light on the laughs. It's certainly not for lack of possibilities - there has to be millions of comedic options available in a movie about a teacher with rubbery morals and a care factor close to zero.

But unfortunately, Bad Teacher comes off as simply mean-spirited and nasty, rather than inappropriately funny or laden with good old-fashioned schadenfreude.

Diaz stars as Elizabeth Halsey, a teacher who's not a fan of kids or other teachers, but luckily she has a plan - to marry her incredibly rich boyfriend that she doesn't really love and give away the teaching game forever.

Before you can say "I ain't sayin' she's a gold-digger...", Halsey is dumped, broke and back at school for the start of the new year, which she intends to spend hungover while her class watches movies.

Soon Elizabeth hits on a plan to get herself out of teaching and on to easy street - raise enough cash for a boob job to help her score another rich fella she can live off for the rest of her life.

The potential in this film is massive, and the cast is actually quite good in their roles. Seeing Diaz playing against type so strongly is refreshing, while Timberlake relishes his dorky role as a substitute teacher from a rich family who becomes the object of Halsey's misguided affections. Segel is also handy as a gym teacher chasing Halsey.

There are a smattering of giggles but for the most part Bad Teacher's humour misses the mark. In the right hands, the swearing, drug-taking, manipulation and stealing could have been funny. But here there is little point to it and fewer laughs, and unfortunately Halsey comes off as impossible to like with few, if any, redeeming qualities, while growing very little as a character.

That movie-makers can make us secretly cheer for serial killers like Hannibal Lector or Patrick Bateman makes you wonder how the people behind Bad Teacher could have failed so badly to get the audience on the side of an attractive disfunctional teacher.

This is a misfire, and although it wants to be the next Bad Santa it ends up just being bad.