How can you tell the target age for "Superhero Movie" is exactly 13 1/2 years? Because most of the jokes are Internet-related.

Facebook, My-Space, YouTube, and everything Apple come in for fond lumps, and when a character says "You're no longer in my Five," it's a giggle for anyone under 20 and crickets for everyone else. This could be the first iComedy.

As such, it's not terrible - splattery business as usual from the folks who gave us the "Scary Movie" franchise. Like its forebears, "Superhero Movie" delivers generic-brand Mad Magazine yuks, the broader and smuttier the better. You don't mind much until the comic inspiration runs dry halfway through.

An anything-goes spoof of the "Spider-Man," "Batman," "X-Men," and "Fantastic Four" movies - but mostly "Spider-Man" - "Superhero Movie" tells the tale of Rick Riker (Drake Bell, of Nickelodeon's "Drake and Josh"), a 98-pound high-school weakling bitten by a genetically altered dragonfly during a school trip. Before you can say "shazam," he's climbing walls and dazzling the citizens of Empire City as the Spandex-clad Dragonfly, a superhero who can do everything except fly.

Director Craig Mazin wrote the script, making this as close to an auteur film as these movies ever get, and one of the producers is David Zucker of "Airplane!" fame. Accordingly, there's a strong genetic strain of that classic in "Superhero Movie," from a flashback cameo by Robert Hays as the hero's unlucky father (he tells the kid to sell Google stock and buy Enron) to Leslie "Don't call me Shirley" Nielsen as Rick's Uncle Albert. Marion Ross plays Aunt Lucille like Mrs. Cunningham from "Happy Days" with a severe flatulence problem.

The cast plays along with game deadpans, in tune with the silly vibe: Sara Paxton as wholesome girl-next-door Jill Johnson, Christopher McDonald as the power-crazed CEO who becomes the dastardly Hourglass, "Star Trek: TNG" alumnus Brent Spiner as a scientist, and Tracy Morgan ("30 Rock") as bald-domed Professor Xavier. Pamela Anderson is briefly glimpsed, sort of, as the Invisible Girl.

The best gags here, though, are topical and extremely rude, from an appearance by Professor Stephen Hawking (Robert Joy), pining electronically for female companionship, to a spot-on parody of Tom Cruise (Miles Fisher) in an online video interview much like his notorious Scientology testimonial. "Superhero Movie" is the kind of film that features a fistfight between Nelson Mandela, Archbishop Desmond Tutu, the Dalai Lama, and the Pope, and dares you not to laugh.

You do - for a while, anyway. The hit-to-misfire ratio is about 50-50, and it tilts further as the plot wears on, not in the movie's favor. "Superhero Movie" would make a decent long-form short on the "Funny or Die" website, but at 85 minutes - 15 of which are outtake-heavy end credits - its powers of amiability wear off fast.