Sanji was a beginner cook in a boat when they were attacked by a pirate with the name of Red Leg Zeff when suddenly both the ships got caught in a storm and sank.
Sanji was saved by the pirates’ captain Zeff after saying out loud about his dream to find the ultimate sea all blue, but although Sanji did not know yet, saving Sanji cost Zeff his leg.
Sanji and Zeff were stranded on an uninhabited island where Zeff gave Sanji a bag of food that should last an average person for about five days, but Sanji distributed it into twenty-five days worth of food.
Since at the time Sanji did not like Zeff, he and Zeff were separated, and they promised only to contact each other if they saw a boat. However, when Sanji finally lost his last piece of bread; he was starved, and he decided to check up on Zeff.
He was surprised to see that Zeff’s bag was full so he decided to steal some food but in the bag wasn’t food, it was a treasure. Later, Sanji finds out that Zeff didn’t eat a single thing all this time, and Sanji also finds out that Zeff had sacrificed his leg to save Sanji Zeff used his legs to fight and he couldn’t be a pirate anymore.
When they both finally get saved, they decide to open a restaurant out in the sea, and Zeff, who was a cook takes Sanji under his wing, and Sanji also grows up in Zeff’s care when finally setting out to sea with the Straw Hat pirates as their cook to also achieve his dream to find all blue.