From audible.com:
"As much as Scalzi has the scientific creativity of a Michael Crichton, he also has the procedural chops of a Stephen J. Canell to craft a whodunit with buddy-cop charm and suspects aplenty - most of them in someone else's body." (USA Today)
John Scalzi returns with Head On, the stand-alone follow-up to the New York Times best-selling and critically acclaimed Lock In. Chilling near-future SF with the thrills of a gritty cop procedural, Head On brings Scalzi's trademark snappy dialogue and technological speculation to the future world of sports.
Hilketa is a frenetic and violent pastime where players attack each other with swords and hammers. The main goal of the game: obtain your opponent's head and carry it through the goalposts. With flesh and bone bodies, a sport like this would be impossible. But all the players are "threeps", robot-like bodies controlled by people with Haden's Syndrome, so anything goes. No one gets hurt, but the brutality is real, and the crowds love it.
Until a star athlete drops dead on the playing field.
Is it an accident or murder? FBI agents and Haden-related crime investigators Chris Shane and Leslie Vann are called in to uncover the truth - and in doing so travel to the darker side of the fast-growing sport of Hilketa, where fortunes are made or lost and where players and owners do whatever it takes to win, on and off the field.