Leo and his friends, Teodora, Don Andrés, Alebrije, Alebrije's cousin, Evasito and the sugar skulls had went to Guanajuato to save Xochitl but, a mummy invasion had awoken.

In this new adventure Leo San Juan, Don Andres, Teodora and the Alebrije go to Guanajuato City in Mexico to stop the mummies, whom inexplicably have awaken, and rescue their friend Xochitl with the help of Luis and a new friend they met. Leo discovers the terrible secret of Rosseau, the richest man in town while the rest of the gang realizes that everything has been a setup.—Achtopa