Dr. McCoy's famous catchphrase first appeared in a classic film
It was potentially first used 33 years earlier.
Few catchphrases are as iconic as Dr. McCoy’s "I’m a doctor, not a…" line from Star Trek: The Original Series. The phrase would go on to live long after the series. Numerous characters from across the Trek franchise and pop culture would reference the line, including The Doctor from Voyager, Julian Bashir from DS9, and many more.
This witty remark may have become a staple of the series, but its origins are potentially from a classic 1930s movie.
Premiering in 1933, The Kennel Murder Case was a mystery film about the murder of a professional dog-show competitor. Helping to solve the case was Dr. Doremus, who first uttered the line “I’m a doctor not a…" for the first time.
The line was used twice throughout the classic film. The doctor would state that he is not a detective and then later a magician.
33 years later in 1966, we would see Dr. McCoy use the same line in The Corbomite Maneuver during the first season. Our favorite Trek doctor would use the catchphrase several more times throughout the series, including the exact magician line used in The Kennel Murder Case.
The lines appear to be identical enough to be more than just a coincidence, though it is unconfirmed if it a direct homage. While we may never know how original the famous line truly was, it'll continue to entertain Trek fans for years to come.