No Plan B (Jack Reacher 27) by Lee Child

In Gerrardsville, Colorado, a woman dies under the wheels of a moving bus. The death is ruled a suicide. But Jack Reacher saw what really happened: A man in a gray hoodie and jeans, moving stealthily, pushed the victim to her demise—before swiftly grabbing the dead woman’s purse and strolling away.
When another homicide is ruled an accident, Reacher knows this is no coincidence. With a killer on the loose, Reacher has no time to waste to track down those responsible. 
But Reacher is unaware that these crimes are part of something much larger and more far-reaching: an arsonist out for revenge, a foster kid on the run, a cabal of powerful people involved in a secret conspiracy with many moving parts. There is no room for error, but they make a grave one. They don’t consider Reacher a threat. “There’s too much at stake to start running from shadows.” But Reacher isn’t a shadow. He is flesh and blood. And relentless when it comes to making things right.
For when the threat is Reacher, there is No Plan B.