My Super Ex-GirlfriendONE of the freshest movie premises of the summer — and one of the best casting choices, Uma Thurman as a superhero using her powers to exact payback on the man who jilted her — are utterly wasted in My Super Ex-Girlfriend<$>.This comedy is so unfunny, it’s like director Ivan Reitman and company had their senses of humour tranquillised from guzzling kryptonite lattés.

After a string of comedy hits in the 1980s and ‘90s including the Ghostbusters<$> flicks, Twins and Dave<$>, Reitman’s output has slowed to a trickle, this latest dud following his 2001 flop Evolution.

First-time screenwriter Don Payne, a veteran writer for The Simpsons<$>, hit on a potentially delightful premise but executes it blandly as My Super Ex-Girlfriend lumbers through dreary sight gags and drearier patter, writes David Germain<$>.

With his aw-shucks plainness, co-star Luke Wilson is a weak and boring counterpart to Thurman. It’s not too believable her wonder woman of a superhero would fall for this sleepy sheep in the first place, let alone care enough to go hell-hath-no-fury ballistic on him after he dumps her.

Thurman stars as Jenny Johnson, whose teenage encounter with a meteorite gave her super strength, the ability to fly and other powers. Toiling as a mild-mannered art curator by day, Jenny moonlights as G-Girl, a hot, chic superhero fighting crime and doing the usual good deeds.Trouble is, Jenny seems to have missed out on the mentoring that taught Superman and Spider-Man that great power brings great responsibility. Needy and neurotic, Jenny becomes a clinging girlfriend to architect Matt Saunders (Wilson), who’s initially thrilled at bedding a superhero but soon decides to break it off over her possessive behaviour.

Jenny vows revenge, especially as Matt begins to romance co-worker Hannah (Anna Faris). A scene where Jenny tosses a live shark at Matt is mildly amusing, but most of her other little retributions are tame and lame.

Thurman is ravishing as G-Girl and alluring in a schoolmarmish way as the mousy Jenny, and she injects far more spirit into the character and dialogue than the script contains. She’s endearingly compulsive as Jenny and boisterously psychotic as G-Girl in reprisal mode.

Wilson is so banal he kind of evaporates alongside Thurman. Even worse, Rainn Wilson as Matt’s know-it-all buddy is given such feeble wisecracks to spout he kind of evaporates alongside Matt.

Faris is forgettable, Eddie Izzard is tossed in to little purpose as G-Girl’s archrival, and Wanda Sykes has a few shrill scenes as Matt’s boss.

In retrospect, Reitman owes so much of his early reputation to Bill Murray, who elevated Stripes, the Ghostbusters<$> movies and even Meatballs <$>to comic heights the scripts probably didn’t merit.

Turn back the clock 20 years and imagine how My Super Ex-Girlfriend might have turned out with Murray and say, Ghostbusters<$> co-star Sigourney Weaver as the spurned ex. That’s a scorned-superwoman comedy we’d like to see.

My Super Ex-Girlfriend, a 20th Century Fox release, is rated PG-13 for sexual content, crude humour, language and brief nudity. Running time: 96 minutes. One and a half stars.

Reitman’s output slows to a trickle