Boomer, the youngest of the Rowdyruff Boys, had always been picked on by his brothers, Brick and Butch, for being single. He'd had a soft spot for Bubbles, the youngest of the Powerpuff Girls, for some time now, but had been too scared to act on it. Times were changing, however, and Boomer would soon have to change with the times.

It started on a warm spring day in Townsville. Boomer had nothing else to do, so he decided to go for a walk. Coming across some railroad tracks, he decided to walk on them. This decision would nearly cost him his life.

Some distance away, an eastbound Amtrak train had just left a station. Its path would take it right over Boomer unless it was stopped. Boomer, oblivious to the danger, kept on walking. The train was still several miles away, but would arrive any minute. Suddenly, Boomer could see it coming. It was too close for him to avoid, however, so it crashed into him at 125 mph. The impact instantly knocked him out.