The Stainless Steel Rat (1961), The Stainless Steel Rat's Revenge (1970) and The Stainless Steel Rat Saves the World (1972) by Harry Harrison.

Omnibus edition of the first three Stainless Steel Rat series. It was explained pretty quickly that stainless steel rat was a metaphor. In this future the galaxy is fairly peaceful and bland. James Bolivar "slippery Jim" DiGriz had a choice in life to go with the flow or to stir things up, get some excitement, live on the edge, making a not honest living. He's the rat, and the stainless steel is the type needed in this space age.

The first chapter introduces us to Jim and his narrow escape from the law. The second he is caught by the Special Corps, who rather than throwing him in jail, enlist him as a field agent. Jim in his training and bored out of his mind, uncovers a warship being built. He is sent on his first mission.

The plot follows sort of a pattern of Jim explaining what he's going to do, and what he expects will happen. A few unexpected things happen, things get worse, he thinks himself out of the jam, or gets outside help, things get better, and so on. Sometimes Jim holds back some of his plan, so that the reader doesn't know the outcome ahead of time.

In Revenge Jim is sent on a mission to Cliaand to find out how they are conquering worlds and building an empire when interstellar warfare is seemingly impossible.

There is a lot of action, the characters aren't very deep, even Jim seems to be straight from a 1940's or 50's Private Eye novel, with the slight twist that he's not law abiding and he's placed in a future galactic civilization. The novels are fun, and even with the small print in my edition the reading didn't bog down.