Watch Supernatural season 5 Episode 12. The title of this episode is "Swap Meat". Gary, a teenage nerd, conjures up a body-switching spell and changes bodies with Sam. Thrilled by his new handsome and built body, Gary (now Sam) investigates a case with Dean and takes advantage of his good looks and age by hitting on women and getting drunk. Meanwhile, Sam is stuck in Gary’s teenage body, dealing with intrusive parents and high school.