Sean Murphy is a character in the 2002 paranormal horror film Ghost Ship. He was a captain of the Arctic Warrior which was saving the wrecks of abandoned ships. He cared a lot about Maureen Epps, who was like his own daughter. He always felt the big responsibility for his crew.
Murphy and his crew were asked about help from Jack Ferriman who found SS Antonia Graza in international waters. Murphy accepted his offer with cutting of the share of Ferriman at 10% of the total price. He was reluctant to take Ferriman with them but he quickly assured him that without it there will not be any deal.
When they arrived to the wreck of the ship, Murphy identified the ship as Antonia Graza as he heard about it and its history. He prevented Greer in calling of the costal guard as he did not want any unexpected visitors and was preparing for repairing of the ship. During the research, he saw the ghost of the captain but he dismissed it as seeing things from overwork. When they found the gold, he noted that they have the right for taking it as they were in international waters. He agreed with leaving of the ship and taking the gold with them.
After the destruction of the Arctic Warrior and the death of Santos, Murphy was feeling guilty for his fate and he did not participate in effort of Epps, Dodge and Munder to repair Antonia Graza. Similarly as Greer, he separated from the others in the captain cabin. He saw the ghost of the captain again. The ghost showed him the picture of the Lorelei from which they saved the gold together with the sole survivor two days before the dissapearance of the ship. Jack Ferriman turned up to be this survivor. Murphy tried to find the others and get out of the ship.
During the way to them, he saw the ghost of Santos who blamed him for his fate. Murphy tried to run away from him and he met Epps. But he saw her as Santos who urged Murphy to kill him. He attacked her and she was not able to stop him. He was knocked down by Ferriman and the rest of the crew locked him in the drained fish tank as they could not trust him anymore.
When Epps found the truth about Ferriman as well, she ran to help Murphy out of his prison, but she came too late. The water got into the fish tank and Murphy was already drowned. He still had the picture of Ferriman.