John Thompson was born in a small town in Maine, on Terra's North American continent in early February in the year 2220. Called 'Jock' by both his family and friends, his Scottish ancestry and solid background in engineering made him one of Montgomery Scott's favorite subordinates. He was given the job of Assistant Engineer soon after being assigned to the Enterprise

Jock was outspoken, sometimes rudely so, with a bitingly sarcastic wit and a tendency to lecture until he passed out from lack of oxygen - or so his last roommate on the Enterprise, Ruth Valley, claimed. His sarcasm, however, hid a deeply caring soul and a gentle, loving heart.

Jock was killed on a landing party on Delta Carinas nearly a year after Ruth came aboard the Enterprise. Something large and carnivorous jumped from a tree and ripped his throat out. His was Ruth's first experience with the death of a fellow crewmember, and she eulogized him as best she knew how - in song.