Gordon and Robbie Tillman are with their folks at their vacation home on Lake Naciemento when they have an encounter that neither of them can at first believe. They are fishing from their dock when they notice a scene below the surface of the lake which appears to be a massacre of a large Indian tribe. A Shaman appears in the scene and beckons them to join him. They stare at the scene in awe until suddenly they find themselves a part of the scene. They can only communicate in sign language but get the message that he wants them to help get rid of the creatures who were responsible for the massacre. How they got to the location is a mystery. They identify a couple of cousins who can cross over to the scene and start to plan to take care of the problem. When a couple of fisherman are killed in the current time by the creatures they discover how the creatures are crossing to their time through a portal. They also discover that killing the creature responsible for the deaths before the event took place negates the action. That is only the beginning of their adventures as they travel back and forth in time over the next 20 years until they discover the reason for this ability. The concluding events bring them full circle and they finally understand why and how they acquired the unusual ability. A little bit of horror, a little bit of fantasy, and a lot of action