Ensign Cortez was a Starfleet officer who served as an engineer aboard the USS Enterprise in 2267. While the Enterprise was under attack by some raiders, Cortez was working at the engineering station on the bridge. On one of the hits the starship took, sparks flew and burned Cortez' hands, forcing Pavel Chekov to take over from him. Chekov summoned Dr. McCoy to the bridge, and McCoy administered painkillers to Cortez' scorched hands. (TOS novel: The Disinherited)