Redshirts
“A redshirt is a stock character, used frequently in science fiction but also in other genres, whose sole purpose is to die, often violently, soon after being introduced … The term comes from the popular American science fiction television series Star Trek, in which security officers wore red shirts…”
An amusing entry on Wikipedia. Whenever there was an extra in Star Trek (the original series) you knew they were going to die in the first five minutes. Now you know what to call the short-lived extras
Article here.
Further reading
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