Mike Nelson rescues an unidentified girl from drowning. The Immigration Department suspects she's an illegal alien. The girl confesses she was towed into the country underwater in a sea sled operated by a ring of border runners.
Before Mike Nelson can investigate the disappearance of two geologists, the sea washes one of them upon the beach. His body bears marks made by the suction valves of a giant octopus. Mike knows an octopus rarely attacks.
Slade finds himself in possession of a key that treasure seekers would kill to get back: the key to the Seven Emeralds of Quetzalcoatl.
