Even Superman couldn't save this movie

OK. It's a real good idea filmmakers have going for them in "My Super Ex-Girlfriend." It's a fresh premise, very inventive, possibly the most original movie concept of the summer. And fabulous casting with the ravishing Uma Thurman as the scorned superhero, using her powers to exact revenge on the mere mortal boyfriend who dumped her. And, it was directed by Ivan Reitman, the brilliant mind behind "Ghostbusters."

So, what could be bad? Apparently, EVERYTHING! Possibly the un-funniest movie I've seen in years, this film has enormous potential to be a lasting, classic comedy and leaves it completely unfulfilled. Like a yawning chasm, unfulfilled. It's as if Reitman and all the writers and actors have had their super-comedy powers neutralized by close contact with some special strain of Hollywood kryptonite.

Matt Saunders, something of an "aw shucks" kind of Everyman, is underplayed for laughs by Luke Wilson. Now, I know this guy is funny. I've seen him be funny. He is not funny in this. And the super villain who has a crippling crush on G-Girl (Thurman) left over from an adolescent sting he suffered at her hands is played by brilliant Brit Eddie Izzard. Normally hilarious, Wanda Sykes has some shrill scenes as Matt's boss but is basically just taking up space, and there's quite a bit of it. Vast, humorless expanses of un-funny space between lame sight gags, idiotic dialogue and plodding plot advancement gimmicks.

Matt's true love interest Hannah (Anna Faris) is quietly mild to the point of practically evaporating off the screen, and even with the super-plot twist at the end that should really amp her up a little, her character is forgettable at best.

Now, Thurman, as a mousy, librarian-ish art curator in glasses and a bad brown wig, is actually almost interesting, mostly because we're used to her kick-butt "Kill Bill" persona and this is clearly a departure from that. Perhaps too much of a departure, I think. Even as the super-hot G-Girl, clad in a confusing array of couture and comic book clothes, she just doesn't have the punch to put this character over the edge.

Over the top, yes. She is neurotic, psychotic and badly over acting all that personal drama all over her love life. So, combine an unbalanced borderline personality disorder with super powers and a boyfriend who bailed on her and … wait, is this supposed to be funny? Not so much: It kind of reads like the revenge fantasy of every girl who's ever been on the wrong end of a nasty break up.