- For other uses, see Kaplan.
In 2267, Kaplan was a member of the nine-person landing party to the planet Gamma Trianguli VI around stardate 3417. A short while after the teams arrived by transporter on the planet surface, both Spock and Hendorff were shot through with spores by what was revealed to be a pod plant, a dangerous form of Gamma Trianguli VI plant life. After Hendorff's death and Chief Medical Officer Leonard McCoy's pronouncement that Spock was in critical condition, Kirk ordered the party to beam back up. When the transporter failed, the party fell victim to a freak storm that was later attributed to the computer that controlled the planet. Kaplan, seeking cover, was killed by a lightning bolt. His body completely vaporized, Kaplan was the second of four security personnel to die on that mission, from the various hazards in Vaal's "garden" territory on Gamma Trianguli VI, and especially troublesome for Kirk as he knew Kaplan's family. (TOS episode & novelization: The Apple)
In a memoir written in the early 2270s, then-Rear Admiral Kirk would remember, as a group, the ninety-six crewpeople (including Kaplan) who died during Kirk's five-year mission as Enterprise commanding officer. (TOS novelization: Star Trek: The Motion Picture)