The Vongola 10th boss, a 27 years old man who was once a useless, clumsy person was given a mission from his advisor -a devious hitman, the strongest of all hitmen- to capture and interrogate a certain bandit -no, that's an understatement, the right choice of words would be a psychopath on the loose- It was a solo mission so he (Tsunayoshi) thought, Reborn, the advisor just wanted to test him. But Tsunayoshi couldn't avoid engaging into battle with the killer for the killer in the hooded cloak was too strong for him,even if he was the Vongola tenth boss. As the killer and the mafia boss fought, the killer vanished and the mafia boss blacked out. Next thing the boss knew, he was on a ship with muscled men. He also found a spiky haired kid, a blonde teenager on a hammock, and an old looking man on a suit.