To date we have 10 Stainless Steel Rat books, plus a few short stories – but the series might never have become a series had it not been for a request from editor Toby Roxburgh, who was then at Walker. He was reprinting – in hardcover – SF books which had only previously appeared as paperbacks. He wanted to reprint the original Stainless Steel Rat novel, and somehow Harry ended up pursuading him to do a new Rat novel as well.
If you haven’t already read it, my interview with Harry Harrison about the Stainless Steel Rat givesw these and other details about the origins and history of the character. You can read it on the Harry Harrison website here.
Here are the covers to the Walker editions of The Stainless Steel Rat and The Stainless Steel Rat’s Revenge, a first hardcover and a first edition respectively. The cover artist is Jack Gaughan.