After the Ghostbusters and Slimer return from a job, a Scotsman enters looking for Ray. He reveals that Ray's uncle, Andrew McMillian, recently died. Ray's not so bothered by this as he never met Andrew (they only exchanged notes on Christmas), but passes out when the Scotsman reveals that Andrew left Ray his castle in Scotland (not wanting to leave it to closer family as they were freeloaders). The Scotsman then explains that the first person to exorcise the ghost that's haunting the castle gets to be the Duke of Dunkeld, and Ray gets the first go.
The Ghostbusters fly to Scotland, and meet the executor of the will, Angus Lennie. He talks to them about the ghost and shows them a memorial dedicating a gruesome battle between the highlanders and the lowlanders. They go to the castle, and that night, Peter gets up to use the bathroom. He runs into Winston and Ray, the latter of whom is being chased by an empty suit of armour. This wakes up Egon, who scans it and confirms it's haunted. Angus explains that the ghost is a personification of the battle.
The Ghostbusters run outside and trap the ghost, only for 723 more ghosts to rise. Angus reveals that it was rumoured that the old ghost was keeping the other spirits in the afterlife, but he thought it was just a legend. He then reveals that the battle ended with the highlanders killing the lowlanders, which these ghosts therefore might do, which is bad news as the Ghostbusters only have two traps. Ray then bikes downstairs and asks the electric company boss for $1000-$2000 worth of electrical equipment.
While Peter, Egon, and Winston try to fight off the approaching ghosts, Ray bribes the villagers to help him with a hundred dollars each. The electric company then lines up a lot of garbage trucks, which Ray sets to suck the ghosts in. He then tells a guy named Mr. Macintosh to bury the trucks until the ghosts dissipate.
Ray then reveals that he learned Angus wasn't the real executor and was instead working for Andrew's freeloading relatives to sabotage his attempt. Ray promises not to call the police, but only if Angus pays for new garbage trucks and stores the trash on his property until the new ones arrive. When the Ghostbusters go home, they receive a bunch of Scottish attire, and Ray also receives a bagpipe, which Peter dislikes.
This episode provides examples of
- All Myths Are True: The "legend" of the ghosts being kept in the afterlife by the red one turns out to be true.
- And I'm the Queen of Sheba: When Ray claims to be the Duke, one of the villagers says, "And I'm Dick Whittington's hat!".
- Arbitrary Skepticism: Angus knew the ghost existed, but he genuinely didn't believe the legend behind the ghost was true.
- Blowing a Raspberry: Slimer blows a raspberry at Peter for insulting him.
- Comically Missing the Point: When Janine hands Egon water, she expects him to pour it onto the passed-out Ray, but Egon drinks it instead.
- Curse: The initial ghost is purported to have been responsible for the devastating battle that killed the other soldiers. He was condemned to haunt the castle, while the others would rest. The guys unknowingly break the curse by trapping him, awakening the other ghosts in the process.
- Dem Bones: The evil Scottish ghosts resemble walking skeletons.
- Everyone Has Standards: After it's explained why trapping one ghost has unleashed such carnage, it's Peter who grabs Angus and angrily berates him for this.Peter: You knew, and you let us do it!
- Evil Laugh: The red ghost laughs evilly once.
- Faint in Shock: Ray passes out upon learning he may become Duke.
- Ghostly Animals: The skeleton ghosts ride on ghostly horses.
- Hope Spot: The first ghost gets trapped... which awakens the others.
- It's All My Fault: While Ray had no way of knowing that the spirits would rise, he considers it his fault since he's the Duke.
- Karmic Jackpot: Ray and Andrew never met, having only exchanged letters at most. However, Andrew still leaves him everything since he was far nicer and more accomplished than the freeloading immediate family members.
- Last-Second Joke Problem: Everything is back to normal and Dunkeld is saved... but Peter is annoyed at Ray's bagpipe-playing.
- Mistaken Identity: The first Scotsman, due to not knowing what Ray looks like, initially thinks Egon is Ray.
- Mocking Singsong: When Peter insults Slimer, he babbles mockingly at him.
- National Stereotypes: The Scotsmen use stereotypical slang like "lad" and "aye", and a few of them wear kilts.
- Oh, Crap!: Winston looks nervous when his proton pack runs out of charge.
- Only in It for the Money: Due to not really believing Ray, the townspeople only agree to help them because he promised them money.
- The Pratfall: When Peter and Winston bump into each other, they fall onto their behinds.
- Pun: When Egon refers to the first ghost as "a live one", Angus says, "No, it's dead".
- The Reveal: Towards the end, Ray reveals that Angus was plotting against him.
- Shout-Out: Peter mocks Ray's daydreaming by calling him Peter Pan.
- Slapstick: At one point, Egon accidentally runs into a wall.
- Status Quo Is God: Ray decides to step down from being the Duke.
- Theme Music Power-Up: The theme tune plays during the scene of the ghosts getting sucked into the garbage cans.
- This Is Gonna Suck: When the other ghosts rise, Winston comments in a resigned way that they look unhappy.
- Water Wake Up: Subverted — Ray passes out, so Janine hands Egon some water to pour on him... but Egon, not getting it, drinks the water and Ray comes to of his own accord.
- Woken Up at an Ungodly Hour: When Ray wakes the villagers, they complain about how late it is.
