9. Spock - Star Trek II: The Wrath of Khan
Who Is He?: Mixed human-Vulcan member of the starship Enterprise, known largely for his highly logical approach to both life and the ship's missions. This causes him to be at frequent loggerheads with Captain Kirk.
How Does He?: The Enterprise's broken warp drive needs to be fixed in order to escape Khan, so Spock volunteers to do it, and yet exposes himself to fatal levels of radiation, dying a hero's death as Kirk looks on helplessly.
Why He Should Have Lived: Though Spock's death initially meant a lot given how well the relationship between Kirk and Spock had been established over the course of the TV show, its meaning is cheapened by the third film, which has Spock revived at the end, restoring the status quo.