Commander James Fletcher is a member of British Royal Navy and MI-6 agent.

After betraying the Nathan James in "Tempest" due to his country's deal with Doctor Paul Vellek, Fletcher learns the truth about Vellek's plans in "Lazaretto" and regrets his actions. After trying and failing to turn Giorgio Vellek against his father, Fletcher uses the Triton's radio to broadcast a message to the Nathan James detailing Vellek's plot and apologizing for his actions, particularly to Sasha Cooper. He is discovered by Vellek and Giorgio and then shot in the head and killed by Giorgio. Fletcher's body is dumped overboard by the Triton crew, but his final message allows the Nathan James to foil Vellek's plot.