A Diamond Bomb Threat

John avoids his father's offer of him becoming a lawyer because of wanting to enter a pool tournament instead, but his father and others are aware of a potential bomb threat that could destroy Earth. John, being unaware of it, becomes entangled with the
daughter of an investigator who had been captured along with his daughter who managed to use John for her escape. John and those captured were given a drug causing memory loss. It occurs about three centuries ahead of our time.