N1. The team decided to go for a swim in the bay side of the island research center when suddenly they were pulled under by a whirlpool. They ended up in an underwater lake inside a cave at the bottom of research center N1. The pendant that Colin's father gave him suddenly started glowing and points to a door. Using the pendant, they were able to open the door and walked their way through darkness right into Blue Noah's (Thundersub) bridge. They recognized a command input panel where Colin spoke the word "Thundersub". Blue Noah was activated and broke free of the island research center N1. Near where Blue Noah was drifting after being activated, Blue Noah's sister submarine – the Tempest Junior – was returning from a test being conducted by Ei Domon (Captain Noah in the English dub) and his crew when they spotted Blue Noah afloat. They discovered that a group of teenagers are aboard the submarine. After the Tempest docked at the bow of Blue Noah, the crew met the youngsters and the Captain learned that Colin's father was Dr. Cromwell Collins who designed the submarine. The Captain also saw Anna – who turned out to be his daughter whom he had bad relations with because she thinks that the captain abandoned her and her dying mother for the sake of duty. Colin and his classmates and Anna were allowed to be part of Blue Noah's crew by serving in Tempest Junior. After a couple of skirmishes with the Death Force – the military arm of Gotham headed by Colonel Jrgens (Colonel Lupus in the English dub), Blue Noah saw the wreckage of a fighter plane containing an unnamed pilot. They rescued the pilot from the wreckage and brought him to Blue Noah for medical treatment. After destroying a Death Force sea fortress using the anti proton gun, the pilot who was rescued from the wreckage came about and talked to Captain Noah. He told the captain that he is Flight Lieutenant Domingo from research center N9 and he was ordered to go to N1 to meet Blue Noah and inform them that they should proceed to N9 in order to upgrade Blue Noah with an Aero Conversion Engine which would make the warship capable of outer space flight. Captain Noah now embarks on a mission to reach research center N9 which is located in Bermuda.