Wilson is a crewman of the ISS Enterprise in Mirror, Mirror who joins Chekov's attempt to assassinate Kirk, then switches sides at the last moment in hope of promotion.
Wilson serves aboard the ISS Enterprise in the mirror universe, seen in the Original Series episode Mirror, Mirror. He is one of the men recruited by the mirror Chekov for an ambush of the captain outside a turbolift.
Chekov promises advancement to those who help him move up by killing Kirk. In the fight Wilson suddenly turns on his fellow conspirators and helps save the man he was meant to murder, just as Kirk's own guards, led by Farrell, arrive.
Wilson explains that Chekov would have made him a chief and suggests that Kirk could make him an officer. Kirk, who is the captain from the prime universe and is learning quickly how this ship works, tells him he is in and then knocks him down.