NOTE: This episode is the second of two Groovie Goolies appearances from 1977's "The New Archie and Sabrina Hour" (aka "Superwitch," aka "The Archie and Sabrina Surprise Package"). Although this was made seven years after "Smog" (and it wound up being the final original outing of the Groovie Goolies gang), we're going to assume for the sake of continuity that it's set before that episode.
On a dark and stormy night, Reggie takes a wrong turn and winds up on the road to Horrible Hall. When the car breaks down, Reggie attempts to fix it, but his always-clueless passenger, Moose, manages to make the situation worse.
Sabrina was looking forward to a quiet weekend at her cousins' castle in the country, but she soon discovers that Reggie and Moose are stranded outside. Drac decides to turn the boys into vampires, but Sabrina begs him not to harm them.
When Reggie and Moose come to the door looking for help, Sabrina hides in a suit of armor so they won't see her.
Always eager to help, Frankie invites the boys in to dry off by the fireplace, but when they realize the fire is provided by a dragon, they try to escape, knocking over the armor and revealing Sabrina's face. Reggie recognizes her, but he's in such a hurry to evade Frankie that he barely has time to question it.
The boys find themselves in the library, where they play a lengthy game of "Young Frankenstein" with a revolving bookshelf.
Sabrina instructs Frankie to get Wolfie and fix the car. Trying to remain unnoticed, she conjures a magic elevator to take the boys outside, but when it doesn't work, she realizes that the lightning storm is interfering with her magic.
The magic elevator crashes through the floor and into the dungeon, where it falls apart, freeing Reggie and Moose.
Moose switches on Drac's pipe organ, which wakes up the Mummy, who instructs them how to turn it off.
Naturally, this freaks them out, but they become so terrified when the Mummy asks them to put the cat out that they shoot up the staircase.
Sabrina decides to check on the progress of the car and realizes Wolfie and Frankie have no idea what they're doing.
The boys make their way into the kitchen, where Hagatha offers them some of her Vicioussoise.
A ghost pops out of the pot and offers them a platter with another ghost inside, who also urges them to try the food.
While running away, Reggie stops dead in his tracks, realizing that he just saw Sabrina. He tries to tell Moose but discovers his dimwitted buddy is long gone.
Reggie wanders down a corridor filled with art and doesn't initially notice Moose standing on a pedestal.
He demands that Moose get down, but Moose informs him that a painting is holding him. Reggie grabs his legs and tugs him free.
The boys slide on a carpet down the banister, but instead of landing on the floor, the carpet rises and suspends them in the air.
Although she knows the storm is affecting her magic, Sabrina attempts to cast a spell to make the carpet take the boys out of the castle. Instead, it wraps them up and ascends to the attic.
The carpet drops the boys, who notice a bat in a rocking chair. "It's just a harmless little bat!" Moose exclaims.
The bat transforms into Drac, who asks, "What do you mean, harmless?" The boys run out the door and find themselves standing on the edge of the roof.
Meanwhile, Wolfie and Frankie tell Sabrina that they've fixed the car, but it's obvious to her that they're delusional.
She frets that her magic won't work properly in the storm, but the guys inform her that the rain has stopped and it's begun to hail. She decides to cast a spell and see what happens.
This time the spell repairs the car. She sends it off to get the boys, so the car goes out of the drawbridge and up the wall of the castle to retrieve Reggie and Moose, who decided to hang off of the ledge to get away from Drac.
The car careens into the sky and lands safely back on the road.
Reggie says that Sabrina was there, but Moose asks what she'd be doing in a house full of weirdos. Suddenly, Drac pops up in the back seat and asks, "Who do you think you're calling a weirdo?"