"The Enterprise Incident" is a third season episode of the American science fiction television series, Star Trek, first broadcast September 27, 1968, and repeated December 27, 1968. It is episode #57, production #59, written by D. C. Fontana and directed by John Meredyth Lucas.

In the episode, the crew of the Enterprise are on a secret mission to steal a Romulan cloaking device.

On stardate 5027.3, Captain James T. Kirk takes the Federation starship USS Enterprise, without apparent authorization, into the Neutral Zone between Federation and Romulan space. Three Romulan vessels decloak and intercept the ship, and Kirk is given an order to surrender. Kirk responds by threatening to destroy the Enterprise if the Romulans attempt a boarding. He is then invited, along with Vulcan First Officer Spock aboard the Romulan flagship. Kirk accepts on condition that the Romulans simultaneously transport two of their officers over as an exchange.

Once aboard the Romulan ship, Kirk and Spock are taken before a female commander who demands an explanation for their intrusion into Romulan space. Kirk claims that instrument failure caused the ship to stray off course, but Spock divulges that the Captain ordered entry into Romulan space, claiming it to be an initiative born of insanity. The Romulan guards lead a furious Kirk, now charged with espionage and railing against the treachery of his First Officer, to the brig. The Romulan Commander orders Chief Engineer Scott to follow the Romulans back to their base but the combative Scott refuses.

In the Romulan brig, Kirk injures himself by lunging against the force field enclosing the cell door. Chief Medical Officer Dr. McCoy is summoned from the Enterprise to attend to him. With Spock in tow, the Romulan commander asks McCoy to confirm Spock's characterization of the Captain as being mentally incompetent and McCoy does so. Upon hearing the Doctor's corroboration, the Romulan Commander orders Spock to assume command of the Enterprise. Kirk, calling Spock a filthy traitor, lunges toward him. Spock instinctively defends himself by using the "Vulcan death grip" on Kirk, who slumps to the floor. McCoy declares him dead.

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