Plague of Pythons by Frederik Pohl — Read

By the morning of the fourth day on the island of Oahu, Chandler had learned enough of the ropes to have signed a money-chit at the Tripler currency office against Koitska's account.

That was about all he had learned, except for a few practical matters like where meals were served and the location of the fresh-water swimming pool at the back of the grounds. He was killing time using the pool when, in the middle of a jacknife from the ten-foot board, he felt himself seized. He sprawled into the water with a hard splashing slap, threshed about and, as he came to the surface, found himself giggling.