Complex sentence: Kukulkan transports Captain Kirk, McCoy, Scotty, and Ensign Walking Bear to his ship, where they are brought to an ancient city, and are told they must solve the puzzle of the city or the Enterprise will be destroyed.
Split into simpler sentences: Kukulkan transports Captain Kirk, Doctor McCoy, Scotty, and Ensign Walking Bear to his ship, where they are brought to an ancient city. Kukulkan tells them that they must solve the puzzle of the city or the Enterprise will be destroyed.