Book excerpt: Once, a shooter walked alone through the front doors of an unsuspecting high school in Burke, Virginia. He was young. Troubled. Tormented. Drowning in a cavernous abyss so deep that light itself seemed no longer to exist. It is an all-too-familiar story these days. After all, once a shooter enters a school or another public space, chaos always follows. Or does it? Once A Shooter chronicles the astonishing story of TJ Stevens, a suicidal high school gunman who unexpectedly experiences a miraculous transformation in the exact moment he is about to execute nine hostages and then himself. All author royalties will be donated to a charity that hosts events for troubled teens.