|Affiliation:||Federation Starfleet Section 31|
|Occupation:||Section 31 Agent|
In 2380, he and Elena were posing as Starfleet command-level officers aboard Starbase 55. ("Particle Mechanics", "Possible Regret") From 2380-2384, Elena and Nelkast were still working out of Starbase 55. ("Dimensions", "A Tholian Encounter", "Transphasic Meltdown", "Forbidden Crossing, Part I")
He was assigned to the Starbase with Agent Elena, where they would both replace Admiral Theseus, whom was considered to be a loose-canon for the organization. Both Elena and Nelkast were ordered to watch the USS Phoenix-X closely, and give them missions for the agency.
The missions of top-secret both he and Elena gave out to the Phoenix-X would usually seem honorable and exploratory for a Starfleet ship, but would always end up serving a deeper more sinister purpose for the organization.
In 2382, Nelkast over-saw the installation of the Temporal drive onto the Phoenix-X at Teketekon station. This was one occasion where the two inseparable operatives were actually separated. ("A Tholian Encounter")