Almost a half-century ago, the great Donald Westlake published a comic mystery novel, God Save the Mark. It’s probably not one of Westlake’s very best efforts (though even a Westlake non-best-effort is awfully good). The “mark” of the title is a reasonably intelligent and likable young man who happens to have one great weakness: He’s a perpetual sucker, an easy target, a credulous victim in a world full of con men and their scams.

I’m not going to spoil your enjoyment of the book by explaining how Fred Fitch, the mark, is saved from himself, though you won’t be surprised that—the title of the novel notwithstanding—God does not intervene on his behalf. Indeed, help comes not from the heavens above but rather from a this-worldly tough woman with a heart of gold named Gertie Divine.