His parents abandoned Cyborg Franky as a child, and the person who saved him was the fisherman shipwright Tom in water seven, who then took in Franky as an apprentice after he saw Franky build a cannon out of scraps lying around. He started learning shipbuilding along with another one of Tom’s apprentices named Iceberg, who is the one who gave him the name Franky since his real name is cutty flam which is kind of weird.
When Franky was twelve, Tom was to be sentenced to death for making the Oro Jackson which is the ship of the pirate king Gold D. Roger, although Tom made a deal so that if he makes the first-ever sea train the puffing Tom, he will be pardoned, so for that, he was given ten years.
The marines were going to let tom off, but he was framed by the CP5 leader Spandam, and that’s when Tom declared that he is glad he made the Oro Jackson, so they take tom to his execution, and Franky was extra mad since Spandam used Franky’s battleships.
The puffing tom was talking to Tom, so Franky took it upon himself to stop the train, but he failed, and he was presumed dead, but he managed to survive by replacing the parts of his body that don’t work with metal scraps he finds at an abandoned ship.
Four years later, Franky returns to see Iceburg when Iceburg gives him blueprints of an ancient weapon called the pluton that has been passed down from master to apprentice for years.
Franky then quickly got followers, and he became the underground mafia leader of water seven, and they were called the Franky family.
When the straw hat pirates came, the Franky family stole two million from them, which they would use to repair their damaged ship.
Overall it caused a huge fight which was stopped when CP7 figured Franky had the blueprints of the pluton, so they kidnapped him and blackmailed the archeologist of the straw hat pirates to come with them.
In the end, the straw hats and the Franky family team up to save them and win the fight. Then Franky makes the straw hats on a new ship called sunny which he bought wood from the stolen two million from, and Franky joins the straw hats as their shipwright.