Director Ivan Reitman’s career hasn’t exactly been going in the right direction of late. After failures like “Evolution” and “Father’s Day” it has become apparent the days of crafting comedic classics like “Ghostbusters” or “Dave” are long behind him. While it goes without saying the new superhero comedy “My Super Ex-Girlfriend” doesn’t change this perception, it also doesn’t make it any worse, this slight piece of romantic fluff perfectly harmless entertainment sure to delight viewers when they run across it on late night cable T.V.

Mild-mannered nice guy Matt Saunders (Luke Wilson) had no idea when he asked out shy Jenny Johnson (Uma Thurman) he’d embark on the romantic adventure of his life. But then, he also never figured breaking up with the girl after he discovers how emotionally unstable she is would put him in such mortal danger. But that is exactly what the architectural project manager gets, the whirlwind romance of his dreams and the break-up of his nightmares only the tip of the iceberg once Matt discovers his girlfriend isn’t the meek, timid wallflower he thought she was.

No, Jenny isn’t meek or a wallflower, and she certainly isn’t helpless, but she is an emotional wreck, and even the fact she’s New York’s most energetic and famous superhero G-Girl can’t hide the fact this woman is slowly falling apart. And she’s going to take Matt with her, Jenny becoming so angry at her former beau she turns her superpowers against both him and his new girlfriend Hannah (Anna Faris) caring less her arch nemesis super villain Professor Bedlam (Eddie Izzard) has set his eyes on her destruction.

“My Super Ex-Girlfriend” is a perfectly cast comedy that has all the potential in the world to become something truly magnificent. For escapist summertime entertainment, this one should be a large bag of popcorn and a giant Diet Coke no-brainer, an exuberantly silly over the top tongue in cheek cheese fest reveling in the best clichés romantic comedies and superhero spectaculars always seem to wallow in. This is the kind of pop entertainment that’s anathema to most film critics, an unabashed guilty pleasure sure to find its way into their DVD libraries only to produce embarrassed stutters when someone finds it there.

That’s what the movie should be, and gosh darn it if the thing doesn’t come ever so close to actually being just that. Problem is, “The Simpsons” staff writer Don Payne’s screenplay is an overwrought disjointed mess relying far too much on scatological sexual humor than it does upon anything else. While it is certainly funny (and definitely a novel curiosity) to finally get a taste of what it might be like to engage in intercourse with a superhero (apparently a person should expect to find their bed broken and halfway through the wall), the novelty wears off pretty quick. Yet here the orgiastic gag comes again, multiple times in fact, and my unfortunate punning aside there’s nothing remarkable or worthwhile about experiencing this kind of foreplay twice let alone ad nausea.

Thankfully, what the picture lacks in inspiration and originality it more than makes up for in casting. Wilson, Faris and Izzard are fabulous, each making the most of their thinly detailed characters crafting moments of truly comic inspiration that sweetly tickled my funny bone. Thurman is even better, emerging from the script’s haggard chaos to create a super heroic character who’s really rather, when all is said and done (and the fish stops hitting the fan), well, sweet. G-Girl may be a bit unhinged, and sure she flies off the deep end after Matt breaks up with her, but Thurman manages to make the woman sadly touching, a life lived in selfless secrecy finally taking its toll upon her social manners.

I wish the film wanted to be more than just an obvious riff on everything we already expect it to be. I wish Reitman had more creative impulses at this point in his career than to just create feature-length sitcoms. I wish a lot of things, but just because I spend so much time channeling Jiminy Crickett doesn’t mean my wishing is going to come to any good. This movie is exactly as it appears to be, for the most part no better and certainly no worse than the rather unassumingly trailers made it appear.

And, strangely, I’m all right with that. This film isn’t rocket science after all, and as long as you fully realize the mess you jumped right on in to is filled with feathery nothingness I can think of a heck of a lot worse ways to spend 90 or so minutes. While I’m not about to urge people to spend good money to see it, if “My Super Ex-Girlfriend” somehow manages to find its way into your Netflix queue or your cable television dial I imagine the film will end up being a date you won’t feel too bad about keeping.