He would kill to win

That's the subtitle, the title is Cruel Games: A Brilliant Professor, a Loving Mother, a Brutal Killing, and yes it is the "true crime" account of the well-known game theorist who murdered his wife.  Here is a review of the book.  Here is an excerpt:

During one of their brainstorming sessions, Gallen wrote down "Game Theory" on his to-do list.  With Robb as their primary suspect, they needed to understand better who he was and what made him tick.  It became Marino's job to do the digging which began with the Penn website, where he easily came across Robb's take-home final for his graduate course in game theory.  Marino read the exam and shook his head.  Perhaps it made sense to economics students, but not to him.  Given Robb's intellect and specialty, the detectives couldn't help but wonder if Robb was playing games with them.

Here is one Amazon review:

She, like many in the media, is quick to draw a connection between
Robb's expertise in game theory and him concocting a brilliant and evil
plan to kill his wife and avoid jail time. Nothing could be farther
from the truth. A game theory professor is very similar to a math
professor. They spend a lot of their time deriving proofs. They don't
know how to get away with a crime any better than anyone else.