Michael Rostov was a crewman second class who served as an engineer aboard the Earth starship Enterprise NX-01. He was an assistant to Commander Tucker.
Rostov was the head on an engineering team that included Crewman Jane Taylor; he was always playing practical jokes on her. (ENT: "The Forgotten")
In January of 2152, Rostov was linked to Captain Jonathan Archer, Commander Tucker, Crewman J. Kelly, and security officer Zabel when they were caught up in a strange, fibrous alien creature's tentacles. (ENT: "Vox Sola")
In February of that year, Rostov piloted several of the command staff back to Enterprise from their shore leave on Risa. (ENT: "Two Days and Two Nights")
Later that year, Rostov attempted to reinitialize the plasma flow, after the Enterprise had been taken hostage by the Wisps' ship, but was unable to because the power grid was not charging. When he reported this to Tucker, he noticed that Tucker was acting "wrong", and reported to Captain Archer that Tucker seemed confused, and, in addition, seemed to think Rostov was his superior officer. Later, when Rostov was ordered to prime the deuterium pumps and fire up the warp injectors, his body was taken over by a "Wisp". When Tucker confronted him and asked him if he had any luck priming the pumps, the Wisp/Rostov stated, "I have no idea how to do that. This engine is very complex." He was later escorted to his quarters, where he remained locked until he was freed of the wisp. (ENT: "The Crossing")
In February 2154, when working on the port impulse manifold, Rostov was knocked unconscious by Lorian, who was stealing the ship's plasma injectors. (ENT: "E²")