Sequel to Universal's The Mummy Trilogy. 1951, the O'Connells go to Peru, because Jonathan owns a beautiful hotel where the wedding of Alex and Lin will be organized. But, at the same time, Professor Hummerton, who leads a sect wanting to bring about the Apocalypse announced by the Incas long ago, resurrects the ancient Priest Tzugelkan, a powerful mummy. Together, they want to find the mystical lost city of Paititi and especially the Fountain of Youth, in order to completely revive it and dominate the world. The O'Connells will oppose this, help with another mummy, the first nice one they meet, Princess Akkala, before going against the guardian of the Fountain... who also could prove to be a valuable ally.