This parody of early 20th century "Hard Boiled Private Detective" novels is instead a short story about 16th century mathematician Gerolamo Cardano.
Its opening paragraphs clearly set the tone:
(quoted from Cardano and the Case of the Cubic)
It was a dark and stormy night in San Francisco, but fortunately, I worked in Milan where things were bright and beautiful. Bright and beautiful, that is until she walked into my office. Her face said that she had a paroblem, then her mouth said it too.
"I've got a problem."
All the while her legs were telling me that I should be the one to solve it, but the rest of her body was saying that she was trouble. Except for her left elbow, which was as quiet as the aluminum pot of cold lamb stew in my refrigerator. Yeah, that lamb stew wasn't saying anything to anybody and neither was her left elbow. That's what had me worried. Girls with quiet elbows can't be trusted. I deduce these things. I'm a mathematician. My name's Cardano.

The story is certainly cute, and when the fictional Cardano finally explains (at gunpoint) how he solved the cubic, he does so with a direct quote from the real proof written by Cardano. However, I find that the story unfortunately does very little to illuminate the mathematics. That is, I doubt that anyone reading it will gain any insight into mathematics or the lives of real mathematicians. Of course, that is not necessarily the goal of all mathematical fiction, and if this one seeks only to entertain then it has surely achieved its goal. (Plus, I suppose there is a good chance that anyone who reads it will, at least, be able to remember that Cardano is famous for his general solution of the cubic polynomial!)
Published in the April 2005 issue of Math Horizons. 