When he began committing crimes, he threw suspicion off himself by briefly pretending another man was impersonating him, showing his 'parents', (really other crooks) to the Flash after the Flash caught him next to a crime scene. He nearly succeeded in killing the Flash after knocking him out with a boomerang, then tying him to a giant boomerang that he fired, which then got sent into space and then fell into the ocean. However, the Flash was able to escape from his friction-proof bonds by quickly vibrating his molecules. He also increased the boomerang's velocity so much he was able to use it to defeat and jail Harkness and the two crooks.