A miner finds an unexplored cavern while mining in Colorado. Archelologists are brought in to study the findings, but someone does not want the world to know about the inscriptions found in the cavern. Dirk Pitt gets involved when an attempt to kill the miner and archeologists surfaces. Another cave is found on an island. Indications are that there will be a large catastrophe that will hit the earth. Dirk Pitt races to find out what it is and when.