The Galaga was originally part of the DHARMA Initiative infrastructure on the Island. There were docking facilities around the Island, including those near the Barracks, the Processing Center, at Hydra Island, and at the Looking Glass station underwater. It was used to travel between destinations on the Island and from the Island to the outside world. There is an underwater beacon that helps the submarine to reach the Island. In 1973, an eight-year-old Ben and his father arrived at the Island in the Galaga along with several others to join the DHARMA Initiative, suggesting it was the main means of long-distance transportation. ("The Man Behind the Curtain") When Sawyer, Juliet, Jin, Daniel, and Miles stopped time travelling, they ended up in 1974. Horace Goodspeed said only DHARMA Initiative personnel were allowed to stay and offered to return them to Tahiti by the submarine. After saving the DHARMA Initiative from Richard and the Hostiles, Horace allowed the five to stay two more weeks until the sub's next departure. Juliet sat at the dock beside the Galaga telling of her intention to leave anyway, until Sawyer convinced her to stay. Mikhail said he arrived on the Island to join the DHARMA Initiative by submarine. Juliet also arrived on the Island in 2001 aboard the Galaga, but the exact circumstances of the journey are unknown as she was kept unconscious from the time she met Ethan and Richard Alpert at an airport presumably outside of Miami until after the submarine had docked at the Island. When she woke up, she found herself strapped to a bunk in the submarine. Ethan claimed that the straps and the tranquilizer were necessary because of the roughness of the travel experience to the Island. Ben has claimed the submarine was the Others' only way of reaching the outside world. When the Swan imploded, the underwater beacon stopped functioning along with the rest of the former DHARMA Initiative communications equipment. This meant that if the submarine left, it would not be able to return. John Locke infiltrated the Barracks and held both Ben and Alex hostage, demanding to be taken to the submarine. Ben later explained that since communications with the outside world were lost the submarine is only capable of leaving the Island, but never returning, and that Jack would be leaving the Island by submarine in a few hours. The result would be the same whether Locke destroyed the submarine or not. All he would accomplish by destroying the submarine would be to keep Jack on the Island. Locke was later taken to the submarine by Alex and planted a C4 explosive. As he left the dock, he surrendered to the Others, but the submarine exploded moments later. In the aftermath, Juliet (who would have left together with Jack) questioned if Locke acted on his own or under Ben's influence, when blowing up the sub, or if he blew up the Galaga, at all.
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