Star Trek - The Original Series - Dagger of the Mind
Kirk and Dr Noel visit the Federations Mental Hospital to deliver supplies. As they do so, a cargo container beamed onto the Enterprise contains a stowaway from the planet but he isn`t a patient. Spock discovers that the stowaway has created a mind control device which was used without any thought for its consequences. Capt. James Tiberius Kirk and Dr. Noel are the next victims.