Croc

Croc, whose real name is never given, is a man hired by Shark Sands to threaten the Hunts' Amazon expedition and prevent them from returning with a valuable collection of animals. Hal gives him the nickname "Croc," due to his snaggled teeth.

Hal first encounters Croc their last night in Quito, where Croc follows Hal through the streets. In Iquitos, Croc tries to steal the Hunts' raft while they are away, and then tries to buy their animals for an unreasonably low price. After they refuse, and depart down the river, Croc hires a gang of men and begins to chasing Hal and Roger down the Amazon. The first time they approach the Hunts' boats, Roger throws a basket of baby snakes on one of Croc's men, allowing the boys to escape.

Later Croc's gang raids and sets fire to a native village. Croc's men are beheaded and their headless bodies sent down the river in a canoe, but Croc escapes. The next day he catches up with Hal and Roger, who have been deserted by their crew. Croc steals their remaining boat, along with all its animals, leaving Hal and Roger stranded in the jungle. Two days later, they catch up with him. Croc nearly defeats Hal in a fight before Roger throws an electric eel at him, but knocking him unconscious. They imprison him in a cage with the eel and a boa constrictor, and turn him in to the authorities in Manaus.

Croc is described as big and burly, with a face like a vampire bat's, and "voice that reminded you of a stone wall with broken glass on top."

Books: Amazon Adventure