The Midnight House by Alex Berenson

CIA agent John Wells returns in a cutting-edge novel of modern suspense from the #1 New York Times-bestselling writer.

Early one morning, a former CIA agent is shot to death in the street. That night, an army vet is gunned down in his doorway. The next day, John Wells gets a phone call. Come to Langley. Now.
(From the YouTube description)
Publisher: Putnam Adult (February 9, 2010)