Max is at home one day when he gets a message from Virgil to head for the town dump. He gets there and is transported to Egypt to investigate several disappearances. People have been vanishing and there is a mysterious door covered in Egyptian hieroglyphics. A female Egyptologist comes by and asks them to come by the museum. That night, they sneak into the museum and find the Egyptologist praising a huge statue of Osiris. She tells him that soon they will have the final part and their plan to fruition. Max accidentally knocks over a plant and the furious lady condemns them to the realm of the ancient dead ("You mean Miami?"). Virgil, Norman and Max fall into the ground and into a huge underground chamber where they meet Anubis, ruler of the dead. Anubis quickly chains them, and then has them wrapped up in bandages as mummies and is about to have them buried alive when Norman breaks loose of the bandages and frees the others. They are chased by mummies, but they manage to escape. Back in the museum, Virgil finds a tablet showing the woman and figures out that she is really Isis trying to resurrect her dead husband, Osiris. They also figure out that Isis is sending out rings to people all over the world. Apparently, one of them is the chosen one that can bring the final part of Osiris to life.
They race back to Max's place and find his mom with one of the rings on. The ring turns Moms hand grey and shriveled. The force leads them to Egypt, where the ring opens up the mysterious door they encountered earlier. Inside, they find a huge stone hand. When they try to stop Max's mom from having her hand cut off in the slot, they are attacked by dozens of severed hands. Max figures out that he is the chosen one and puts his hand along with his moms into a slot and the ring vanishes, but the giant stone hand comes to life. Norman attempts to stop it, but it escapes out into the desert where it joins other stone body parts to reconstruct the body of Osiris. He comes to life and Max tries to stop him from destroying the world, which is what Isis wants him to do. At the last moment, Osiris tells Isis, that it is their duty as gods to serve mortals, not to destroy them. That she has lived among humans as a human for so long that she has become bitter and hardened by the troubles of the world. Osiris promises to start a new life with Isis as they both walk off into the desert.