"The Naked Time" is an episode of the American science fiction television series Star Trek. It was first broadcast September 29, 1966, and repeated on April 27, 1967. It is the fourth episode of the first season, written by John D. F. Black and directed by Marc Daniels. The story has a sequel in Star Trek: The Next Generation, the episode "The Naked Now".

In the episode, a strange affliction infects the crew of the Enterprise, destroying their inhibitions.

On stardate 1704.2, the Federation starship USS Enterprise, under the command of Captain James T. Kirk, arrives in orbit around the dying planet Psi 2000. Though their mission is to observe and document the planet's breakup, they have also been tasked to locate a research team on the planet that had not been in communication with Starfleet for months. A landing party led by Mr. Spock beams down, finding the life support system of the researchers' observation post shut down and the team frozen to death in bizarre situations, such as fully clothed in a shower, seated at a control console as if nothing was wrong, as well as one woman who was strangled. One Enterprise crewman, Lt (junior grade) Joe Tormolen, removes his environmental suit glove to scratch his nose and comes in contact with a strange red liquid. The landing party is beamed back to the ship and quarantined by Chief Medical Officer Dr. McCoy. McCoy finds no medical issues with them and allows them to return to duty.

After returning to the Enterprise, going through decontamination and being cleared by Dr. McCoy, Tormolen begins to exhibit mental health issues, prompting Mr. Spock to observe Tormolen has a higher than normal quotient of self-doubt. He acts irrationally, expressing hostility towards other crew members in a crew lounge. He threatens Lieutenants Sulu and Riley with a knife before turning it on himself. His wound is minor and not life-threatening, but in Sick Bay he dies after a successful surgery, to McCoy's bewilderment.

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