While on a gambling trip to the casino on the planet Cassylia, he is challenged by a man named Kerk Pyrrus (who turns out to be the ambassador from the planet Pyrrus) to turn a large amount of money into an immense sum by gambling at a government-run casino. Some planet in the galaxy must -- by definition -- be the toughest, meanest, nastiest of all. If Pyrrus wasn't it . . . it was an awfully good approximation I started this story in an old issue of Astounding Stories that was kicking around - and was very happy to find the rest of it on Kindle. A quick read, really a novella. A solid page turner with lots of action, fun plot twists, and a satisfactory ending. If you like old Heinlein's I think you will like this.