Kidnapped (sort of)

While Jason, Piper and Leo set out on their quest, Percy was in a slumber, or so Hera says. But Hera was lying. Instead, Percy was sent into a world not too different to the demigod's one. The wizarding world. Watch (or read) as Percy encounters the Golden Trio, The Triwizard tournament, and Puking Pastilles. (Reading SoN and TGoF will ensure that you'll understand more stuff)