Rhys Darcen was the leader of a group of Human Augments living on Tagra IV in the 24th century. He had served as an agent of Section 31 in 2374 until the agency had decided against immediate use of a biological agent in the Dominion War. He and his fellow augments then continued to research the virus on their own, eventually planning to target the Cardassian settlement on Ventani II. (Star Trek: Lambda Paz: "A Cause of Greater Worth")