Keith Trent and Sybil Morton, famous treasure hunters of lost nations, don't get along very well with each other. However, they are forced to join forces to work for a mysterious rich man, Mr. Dante, who is obsessed with finding a certain artifact known as the Heart of Alantis. Descending into the legendary treasury of the abandoned castle Runorok, Keith and Sybil will have to survive betrayal, meet an amazing people of gremlins, take part in a real battle and overcome many deadly dangers on the way to uncovering the secrets of an ancient artifact and the secrets of the mythical Gremland.