A relaxing spa getaway evolves into a prehistoric panic when Scooby-Doo and the gang uncover the horrible Phantosaur, an ancient legend come to life to protect hidden treasures buried in secret desert caves. But this scare-a-saurus doesn’t stand a chance with Shaggy around, after he finds his inner hero with the help of new-age hypnosis. Like, it makes him more brave and less hungry! When the Scooby Doo gang encounters the horrible Phantosaur, they investigate to find out what's really behind this prehistoric haunting.