By 2364, she was inserted into the United Federation of Planets where she masqueraded as a Vulcan ambassador going by the name of T'Pel. That year, she attended a meeting with various powers in secret to discuss the recent attacks on the outposts along the Romulan Neutral Zone. She was accompanied by Sarek, Spock and Samuel Robert Fox when they met their Klingon, Romulan and Cardassian counterparts. (TOS - Vulcan's Soul novel: Exodus)
In 2367, she was stationed on the USS Enterprise-D under the command of Captain Jean-Luc Picard in part of a Starfleet initiative to bring peace between the Federation and the Romulan Star Empire. While attempting to transport onto the IRW Devoras, the Romulans faked her death in a transporter accident allowing them to recover their agent while making it appear that the ambassador had died. Captain Picard later followed the Devoras believing that the Romulans had abducted their ambassador whereupon he learnt of the Romulan deception. (TNG episode: "Data's Day")
During Admiral Norah Satie's trial to find out any suspected spies in Starfleet, she noted Subcommander Selok's infiltration of the Federation as proof of her criticism of security procedures. (TNG episode: "The Drumhead")
While within Federation space, Selok managed to acquire a special computer access isolinear chip that allowed an individual to bypass the security lockouts on Starfleet computer databases. This chip was provided to Commander Valak in 2368, allowing him to access the Enterprise's computer systems after he had captured the ship. He was looking for information about Hermeticus II which was located in the Romulan Neutral Zone and was classified as a quarantined world in Starfleet records. This information made the Romulans suspicious, believing that a military base was present in the region. (TNG novel: The Romulan Prize)
Selok survived the Hobus supernova and by 2409 had been promoted to full commander. She was in charge of a research outpost in the Vendor system developing countermeasures against Undine infiltration of the Empire when it came under attack by a Federation starship that had been misled by the Zelle Undine into thinking the Romulans were developing banned weapons. Selok was killed defending her space station. (STO - Romulan Mystery mission: "Divide et Impera")
- "Divide et Impera" was among the missions removed from Star Trek Online as part of a revamp of the "Romulan Mystery" episode on 29 January 2015, and Selok no longer appears in the game.