Catspaw

Sulu, Scotty and Jackson explore Pyrus VII, and then Jackson calls the ship, "one to beam up". He materializes dead, and a sepulchral voice threatens Kirk, saying his ship is cursed! Beaming down, Kirk discovers his men enslaved by strange aliens, who have created a Gothic castle and other artifacts straight from Halloween. But their power and threat are real - they are from a place so alien, that the sensations of this universe are intoxicating. If not stopped, they pose a grave threat to the Federation.