An engineer aboard the U.S.S. Voyager, Carey served under B'Elanna Torres. In 2371, Carey was briefly named acting chief engineer when the original officer in that position was killed during the ship's violent passage to the Delta Quadrant. He was disappointed when Captain Janeway later named Torres for the position of chief engineer, but he soon recognized her superior abilities.
Lt. Carey had a wife and two small sons back home, but sadly never reunited with them after Voyager got lost in the Delta Quadrant. He died in 2378, during a hostage situation, on a planet that had been devastated by antimatter radiation caused by contact with the Friendship 1 probe. Carey was to be released to Voyager in exchange for food and medicine, but the leader of the captors shot him through the heart just before he transported.
Carey arrived in Sickbay, dead.
In the timeline before Voyager's launch, while she was still under construction, Carey briefly flirted with a time-traveling Seven of Nine. Seven encountered Carey while searching the ship for a weapon -- sent from the future -- that Seven had to prevent from destroying Voyager.
One of Carey's hobbies was model building. When he died he had been working on a Voyager version of a "ship-in-a-bottle," and only had one nacelle left to complete it.