Lock In, by John Scalzi

In the near future, a mysterious virus called Haden's syndrome has swept the world, leaving many people with "lock in."  They are fully aware, but fully paralyzed.  Some use Integrators, people who allow someone with Haden's to remotely control their body to experience life in the world.  Other Haden's sufferers use Threeps, android-like bodies which they remotely control.  In Lock-In: A Novel of the Near Future, John Scalzi sets a murder mystery in this world of Haden's.

Chris Shane is a rookie FBI agent.  He was a famous Haden's patient, as he was just a child when he got it, and his father is a famous athlete, wealthy businessman, and aspiring politician.  He teams up with veteran agent Leslie Vann to investigate a murder that has ties to Haden's, politics, and the future of the disease.

Scalzi wastes no time letting the reader acclimate to this world of Threeps and Integrators.  But in the course of the story, it starts to make sense.  The complexity comes with keeping up with one Integrator who serves as a host for multiple Hadens, or with a Haden, like Shane, who uses multiple Threeps.  It makes travel a breeze; though based in D.C., he can be onsite, interviewing witnesses in Arizona, in seconds.  It must be unnerving for non-Hadens to try to figure out who they're dealing with day-to-day.

In one sense Lock In is a pretty basic murder mystery.  The fun of it is the mind-bending use of Integrators.  If someone who works as an Integrator commits a murder, how can investigators tell if the Integrator or the Haden using the Integrator is culpable?  Shane digs into this, but discovers a much deeper plot and complex motives to explore.  The resolution and the climax comes about pretty quickly and maybe a little too easily, but the ride is fun getting there.