Master Sergeant William Chase is a bomb disposal expert in the US Army, and a gifted martial artist. Stationed in Afghanistan, a routine day quickly becomes the challenge of his life as he is tested to the limit by a new insurgent threat. Chase overcomes a gauntlet of tactics the enemy throws at him, until he is badly injured when faced with an impossible decision. He is rescued and evacuated by his team, now faced with a long road to recovery and learning to adapt to life with physical limitations. During his recuperation he is made a candidate for an experimental new program, and is sent to work with a top doctor in New York. There he must overcome his injuries before he can work with the specialists on their new prototypes, and learn to embrace new technology to regain his independence. While Chase settles in to life in New York, an all too familiar threat appears as an illusive bomber threatens the city with a series of ruthless escalating attacks. Realising that the terrorist is using the same techniques he saw in Afghanistan, Chase reaches out to the NYPD Bomb Squad. At first sceptical, the Bomb Squad comes to embrace his experience and invites him to join them as a consultant. Still adjusting to his new life and limitations, he must overcome his physical challenges to help stop the terrorist threat. Killswitch will appeal to readers who enjoy action-adventure stories with a crime or military twist, as well as a technology angle. It is an origin story of sorts, as Chase learns how to adapt to his new post-military life.