''Set a thief to catch a thief'' goes the old saying.

And when you are the richest man in the Universe and someone is systematically robbing your various banks blind you''d better set the best thief ever to catch your thief. After all, even at four million credits a day plus expenses, you can afford him. Enter Slippery Jim DiGriz.

And that''s how it all began for Slippery Jim and his wife, the ever deadly Angelina; persuaded from a life of stockmarket dabbling and picnicking by the hover tanks, hard cash and outright flattery of undoubtedly the richest and probably the oldest man alive; Imperetrix Von Kaiser-Czarski.

It would have seemed rude to not take the job and after barely four weeks (at four million a day) of watching the latest in computers (courtesy of son James) sift through the available evidence Jim has his first lead. Each time one of Kaiser Czarski''s banks is robbed there is a circus in town.

And as Jim knows full well, you don''t find out about a circus by going to it. You join it...