Dr. Cornelius and his mate Zira are the "good apes" in the 1968 sci-fi film Planet of the Apes. Dr. Cornelius is a chimpanzee archaeologist who is sympathetic to human astronaut George Taylor (played by Charlton Heston). Cornelius was played by actor Roddy McDowall in the 1968 film and in the sequel Escape From the Planet of the Apes (1971), in which Cornelius and Zira venture to modern-day Earth. In an earlier 1970 sequel, Beneath the Planet of the Apes, Dr. Cornelius was played by actor David Watson.
In later Planet of the Apes films, Roddy McDowall also played Cornelius’s son Caesar… Cornelius is not featured in the 2001 Tim Burton remake of The Planet of the Apes.