One of the ways Donald Westlake kept his Parker novels fresh was to vary the the success his man had as a professional criminal. Sometimes the magic worked, sometimes it didn't.
Plunder Squad is a long (for a Parker novel) and intense study of how things can go wrong in trying to plan and execute a robbery. Not anywhere as easy as you thought.
Parker is near broke and in bad need of money. As often happens he's forced to deal with people who overestimate their worth as professionals. In this novel we meet a number of them. We also meet a woman who is familiar to readers of Parker books, the sullen horny slut who has affixed herself to the man who has the idea for the heist. Parker knocks several points off the man's score for even having her around. Inevitably she means trouble not just for her honey bunny but for all of them involved in the robbery. She is contrasted, later in the book, by the crisp, pretty, bright young woman who is a helpmate to her criminal boyfriend.
Plunder Squad is a maze of false starts and bad turns. The heist Parker eventually settles on is complicated and requires the kind of skill and oversight only he can bring to the job. As usual the story is enriched by all the men involved, each with different needs and capabilities. And with different degrees of trustworthyness. In a book of this length you really get into Parker's head and pick up on his paranoia and general distrust of those terrible creatures known as human beings.
This is a major addition to the Richard Stark canon, a relentless and often bleak look at life on the wrong side of the law. Though in the Stark books cops often have fewer scruples than cons.