Conan ran up to his grandpa and showed him a half-eaten fish he found in their fish preserve. It was the work "White Nose", a great white shark that roamed the waters around Remnant Island. Conan decided he had had enough and wanted to challenge White Nose (!)
He dived into the sea and sure enough White Nose was just nearby. He provoked White Nose and it chased after him. Armed with only his harpoon, Conan eluded White Nose by swimming among the submerged pre-war buildings. When he made sure that White Nose would chase after him no matter what, Conan headed towards a spot above which he had made a falling-rock trap. White Nose took the bait and was instantly buried under a pile of rocks. Conan thought he got White Nose finally but when he tried to examine it more closely, White Nose revived and chased after him, with blood in its eyes. Conan swam for his life and took refuge on top a rock outcrop above water. This didn't stop White Nose, who leaped out of the water and attacked Conan with its razor-sharp dorsal fin. Conan blocked the attack with his harpoon, breaking it into two. Conan realized he wouldn't be able to block another attack with the broken harpoon, so he poised himself and when White Nose jumped out of the water again Conan leaped into the air and plunged the harpoon right into White Nose's heart. White Nose and Conan went down together into the water, their descent finally halted when White Nose hit the dead end of a tunnel.
Grandpa carried the girl back to their house and took care of her. The next day the girl woke up early and walked out of the house towards the seashore. Conan followed her and saw her talking with terns. The girl also saw Conan and told him that her name's Lana and she came from a distant island called High Harbor. Conan was fascinated by the fact that there are hundreds of people living on High Harbor, since the only human beings he knew were his grandpa and a few others... Suddenly a plane appeared in the sky and Conan thought it's a bird. But Lana told him to hide since that was a hydroplane from Industria and they're here to look for her...
Conan's grandpa also saw the hydroplane from his house and he ran to greet them, thinking that finally he could rejoin the other survivors of the war. But when he saw uniformed Industrians emerge from the hydroplane with weapons in hand, he knew they were not friendly. The Industrian commander Monsley told Conan's grandpa that they were looking for Lana ad ordered him to gather the inhabitants of the island for questioning. Conan's grandpa led them to his house and took out a rocket launcher from his room. He threatened to fire it unless they leave the island. Mosley backed off but one Industrian soldier fired at grandpa. The bullet hit the rocket grandpa's holding and it exploded. Conan and Lana were watching from a distance but when Conan saw his grandpa's hurt, he ran towards the house. The warhead of the rocket meanwhile flew off and struck the ground near where Lana was hiding. Lana ran and was captured by the Industrians. Conan hurried back to the house and saw that his grandpa was seriously injured. Grandpa told Conan to go after Lana and to save her. The Industrians took Lana on board the hydroplane Falco and was about to take off, when Conan leaped and landed on top the wing of the plane. The plane took off with Conan still hanging on the wing...