Sounding more like a prog-rock concept album than a kid-lit fantasy franchise, this CGI-congested origin episode—adapted from Rick Riordan’s five-book series—imagines a world in which director Chris Columbus never left the Harry Potter franchise after the first two installments. J.K. Rowling’s empire-building formula clearly comes to mind in the American guise of Percy (pretty-boy du jour Logan Lerman), a New York City teen with a bleak home life, who is unaware that heroics and special powers run in his blood. His deadbeat dad is Poseidon! Sorry, wizardry lovers, this is Greek mythology not-so-cleverly contemporized (i.e., Hermes’s winged sandals appear as Chuck Taylors)—though if you squint, Camp Half-Blood could stand in for Hogwarts, hellhound owner Hades would be Voldemort, satyr buddy Grover and Athena’s daughter, Annabeth, are the new Ron and Hermione, and so on. Some of the cameos along the Hydra- and Minotaur-filled odyssey are unexpectedly amusing (Rosario Dawson plays Persephone as an unsatisfied sexual predator; Uma Thurman slinks more than the snakes in her Medusa coif), but, like Percy himself, the film doesn’t have any traits that qualify as having an actual personality. Even so, as long as the kiddies aren’t too upset by the major liberties reportedly taken with the source material, it might be enough to distract them until Harry returns.