The Fractal Murders

Jane Smythe, a math professor specializing in fractal geometry, is shocked to learn that three professors with the same specialty have died amid mysterious circumstances. That's where Pepper Keane, an ex-Marine turned PI with an encyclopedic knowledge of rock 'n' roll, comes in. He finds himself attracted to Professor Smythe and is determined to discover the root of these incidents. At first, he can't find any evidence that the three dead mathematicians even knew each other.
But Keane, with the help of his hacker best friend and exercise guru brother, continues to dig. Suspects begin to appear and then multiply as they race through the rocky terrain of Colorado to Mexico, Boston, and Nebraska - with the main suspect an FBI agent who is also Keane's worst enemy.