"The Savage Curtain" is a third season episode of the American science fiction television series, Star Trek, first broadcast on March 7, 1969, and repeated July 1, 1969. It is episode #77, production #77, written by Gene Roddenberry and Arthur Heinemann, based on an original story by Gene Roddenberry, and directed by Herschel Daugherty.

In the episode, aliens force Captain Kirk and First Officer Spock to join forces with "Abraham Lincoln" and "Surak" to battle villains in a contest between good and evil.

The Federation starship Enterprise arrives at the volcanic planet of Excalbia to conduct a geological survey. Sensors curiously pick up the presence of carbon-based life on the surface which Science Officer Spock deems impossible owing to Excalbia's extreme volcanism. Suddenly, the image of a seated Abraham Lincoln appears drifting toward the ship on the viewscreen. While Spock is skeptical that the figure cannot possibly be the real president, Kirk extends full presidential honors to the former leader of the United States as he transports aboard the ship. The president appears to be human, claiming to be "all too human". Lincoln has no knowledge of technology past the 19th century, but is somehow familiar with the Vulcan philosophy of Nom (meaning "all"). Lincoln invites Kirk and Spock to accompany him down to the planet, as a patch of "Earthlike" condition appears on the planet. Kirk accepts despite objections from Chief Medical Officer Dr. McCoy and Chief Engineer Scott. Lincoln reassures them that they will be perfectly safe.

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