Krissy Kristy, a TV music news reporter, is broadcasting live from the spot where music group Rude Boy and the Ska-Tastics died in a plane crash thirty years prior. She began interviewing former Ska-Tastics' manager Ian Hope.
Krissy: Set, Krissy Kristy here with your music news report. Holla! I'm standing on the very spot where one-hit wonders Rude Boy and the Ska-tastics totally ate it thirty years ago in a gnarly plane crash.
She shows the camera a picture of Rude Boy and the Ska-Tastics.
Krissy: See? That's them, like, from before they were dead. And this oldy oldster is Ian Hope. Mr. Hope, you were the Ska-tastics' manager. Tell us, what went down on that tragic night?
Ian: I remember it like it was thirty years ago. It was voodoo. Rude Boy and the Ska-tastics were cursed. Cursed to plummet to their doom on that fateful night. The night that ska died.
A zombified hand grabs Krissy's leg as Rude Boy and the Ska-Tastics come back from the dead as zombies, attack Krissy and Ian. Shaggy and Scooby, watching at home, freak out when they see the broadcast signal cut out during the attack.
The next morning, the gang was at Grooves from the Grave investigating what happened last night.
Shaggy: Like, does every bit of scary news have to be followed up by an immediate "Let's go investigate"?
All: Yes.
Martha Quinn comes over.
Martha: Welcome to Grooves from the Grave. I'm Martha Quinn, owner and proprietor. Can I interest any of you in a third-generation bootleg of Scrooty Palidies' forgotten Christmas album?
Daphne: No, thank you.
Martha: It was recorded in Esperanto.
Velma: We were wondering if you could help us.
Fred: Have you ever heard of a band named Rude Boy and the Ska-tastics?
Martha: Heard of them? You're kidding me. I have every record they ever released right here in the store. Of course, they only released one. Their biggest and only hit, "Graveyard Ska, Inc."
Martha plays it.
Velma: Jinkies. That is catchy.
Martha: Hang on. I've prepared a slideshow on every music group from the last sixty years. Rude Boy and the Ska-tastics. Poor Rude Boy could never quite ride the fame train the way he wanted, so it's said that he turned to voodoo magic to further his career. He cast love spells on the audience. He cursed other bands. Once, he even cast an enchantment of never-ending pain on a synthesizer. Real crazy stuff. Rude Boy always said he would come back from the grave. And now, it looks like he has.
Shaggy: Zoinks!
Scooby: Doesn't anybody ever stay dead around here?
Y/N: Apparently not.
Night came and at the Tiki Tub a woman was singing.
Woman: If my lips could only say the pretty words that I feel in my heart if my voice could make the sound I would tell you how I love you and we'd never be apart love was just one look into your face my mind starts to drift right into space and the words get stuck in my throat, the words get stuck in my throat.
Suddenly smoke appears and the zombies grab the woman and pull her into the ground as Rude Boy and the Ska-Tastics appear.
Rude Boy: one, two, three, four!
They begin to play their song.
Rude Boy: Dance!
Everyone there is forced to dance to their new tune. The zombie band departs just as Sheriff Bronson Stone and his deputies arrive, but the victims cannot stop dancing.
Sheriff Stone: Freeze! Nobody move a muscle!
They continue to dance.
Sheriff Stone: I said freeze! Oh, come on, people!
Soon after, multiple ambulances arrive at the hospital as the gang got a call from Mayor Nettles.
Fred: I haven't seen this many ambulances since that time Scooby thought he had the mange.
In a flashback, Scooby was on a hospital bed as the gang surrounds him.
Shaggy (Flashback): Stay with us, Scoob! Like, don't go into the light!
Scooby (Flashback): Raggy, is that you? I'm so cold. I'm so...
Scooby then burps.
Scooby (Flashback): That's better.
Daphne: Well, if Mayor Nettles called us down here, it must be something really bad.
Velma: Very bad.
They exit the van.
Scooby: I'll catch up with you guys later.
Scooby walks alone.
Daphne: Where's Scooby going?
Shaggy: Where he goes every day, to visit Nova.
Scooby goes into another room and visits Nova.
Scooby: Hello, Nova, my angel. I see you got the flowers I sent. And the bones, and the Scooby snacks. Don't worry, Nova. I'm here, right by your side forever. Of course, sometimes, I'll have to get treats, or go to the bathroom, but otherwise, I'll be here.
The PA goes off and Shaggy voice is heard.
Shaggy: Will Dr. Scoobert Dooby Doo please report to the ICU? Dr. Doo, to the ICU.
Doctor: Please, don't play with that.
Shaggy: Sorry.
The others see the citizens and they continue to dance.
Mayor Nettles: These citizens were found at the Tiki tub. They're dancing, and they can't stop.
Y/N: That dance is called skanking.
Daphne: It's how you're meant to dance to ska music. And you said dance class was a waste of time.
Velma: Oi. Doctor, what's the prognosis?
Doctor: If we can't find a cure within twenty-four hours, they will dance themselves into a permanent cataleptic state.
One of the citizens fell to the ground, collapsing.
Doctor: They will become zombies for the rest of their lives!
The gang go to the cemetery where Rude Boy and the band were buried to look for clues.
Velma: This is the graveyard where Rude Boy and the Ska-tastics are buried.
Shaggy: Like, why do we always have to come to spooky places at night?
Scooby: Yeah. Why don't we come back tomorrow, after lunch?
Shaggy: Or never?
Daphne: Guys, those poor dancing people can't wait until tomorrow!
Y/N: They're counting on us to save them.
Fred: Keep searching, gang.
Shaggy: All I'm saying is for once, I'd like to go into the run-down mansion or the haunted crypt during daylight, when it's not so spo- zoinks!
Shaggy accidentally falls into Rude Boy's grave.
Daphne: It's Rude Boy's grave!
The coffin is then knocked on.
Shaggy: Like, I think there's somebody home!
The coffin opens revealing Ian tied up with tape on his mouth.
Shaggy: It's Mr. Ian Hope, Rude Boy's old manager!
They pick him up from the coffin as they help Shaggy.
Fred: Did Rude Boy do this to you?
Velma: Where is he?
He tries to speak but can't because of the tape.
Scooby: Uh, he's... standing? He's standing right. Uh! oh! He, he, he! He's standing right behind you.
They then see Rude Boy behind Scooby.
Scooby: Uh-oh.
The ground breaks as the other members of the Ska-Tastics grabs Velma and drags her but is saved by Fred and Daphne as Scooby bites the arm. The Ska-Tastics then rise from the ground on their undead motorcycles.
Shaggy: Like, run!
They all run as the Ska-Tastics chases them. Fred hides behind a tombstone and sees a shovel and uses it to knock one of the zombies off their bike.
Fred: You just got IT-ed improvised trapped!
He joins the others as the zombie gets back on his bike and joins the other zombies and drives towards them as Rude Boy blocks the way and drives towards them when Shaggy and Scooby drive in with the Mystery Machine.
Shaggy: Get in!
Shaggy drives off with the others as the zombies chases them into town and they avoid traffic.
Scooby: I can't look!
Shaggy: Like, me, too!
Fred: Pull it together, you two! They're on our tail!
Fred continues to drive until they lose the zombies.
Fred: Well, thanks to some incredibly expert one-handed driving, we lost them.
Velma: Hmm. Perhaps a little too easily.
The gang return to Grooves from the Grave to speak with Ian.
Ian: Rude Boy? Rude Boy has come back from the grave. He's bringing ska back to life.
Scooby: Yeah, by turning people into dancing zombies.
Daphne: Mr. Hope, you were the Ska-tastics' manager.
Y/N: You guys traveled everywhere together.
Velma: How come you weren't on that plane with them when it crashed?
Ian: Um, I missed the plane because of uh, a bizarre laundry accident. Yes.
Martha comes in with a book.
Martha: I did a little research. According to my "Encyclopedia Musica," this isn't the first time people have been afflicted with dancing sickness. The dancing plague of 1518 struck Strasbourg, France, where hundreds of people danced themselves to near-fatal exhaustion. Some say it was caused by listening to cursed and evil music.
Hearing ska music coming from outside, they all exit the store and discover that Rude Boy and the Ska-Tastics are performing on the City Hall roof.
Fred: It's Rude Boy!
Velma: Quick, cover your ears!
Rude Boy: Dance!
Martha: We have to Fight this musically! We need Ultimate power chord!
Martha and Ian are infected as they dance as Fred, Daphne, and Velma struggle to cover their ears.
Fred: I'm fighting it, but I can't resist their catchy use of Caribbean mento and calypso with American jazz and rhythm and blues!
Daphne: Y/N, Shaggy, Scooby, why isn't it affecting you?
Scooby: I'm a dog. Music is just noise to us.
Shaggy: And, like, you've heard me sing. I'm totally tone deaf.
Y/N: I've heard Shaggy sing, I've heard worst.
Velma: Y/N!Shaggy! Scooby! You're our only hope! It's up to you to save the town! It's up to you to save us!
They then fall victim to the music and start dancing.
Shaggy: Like, zoinks!
Back inside the store the three watches as everyone dances.
Shaggy: Like, what do we do, Y/N and Scoob? Everyone in town is a total ska zombie, and we have to save them! Like, we don't know anything about music!
Scooby: We don't, but we know people who do.
Shaggy, Scooby and Y/N: The Hex Girls!
The trio don disguises to sneak onto a yacht where the Hex Girls are playing for a private party.
Y/N: Shaggy, are you sure this is a good idea?
Shaggy: Y/N, we're crashing a private party on the yacht of a rich sheik, and these are, like, the best disguises ever.
Y/N: Well, I won't say the best disguises ever...
They then sneak onto the yacht and see the Hex Girls.
Thorn: Good evening! We're the Hex Girls, and we're here to rock!
Shaggy: There they are! Come on!
Hex Girls: Who do voodoo? We do voodoo. Who do voodoo? We do...
Shaggy: Luna! Thorn! Dusk! Rock out!
Hex Girls: Who do voodoo? We do. We do. We do, we do...
Y/N and Scooby see the plugs and go over.
Scooby: Which one's the speakers?
Y/N: Let's pull them all.
They pull the plugs and the speakers cut off the show as Shaggy yells.
Shaggy: We have to stop zombies from taking over the world!
Soon after, the Hex Girls meet the trio outside.
Luna: Rude Boy and Ska-tastics, back from the dead, heavy.
Shaggy: Like, what's with the original get-ups?
Thorn: Some of our fans prefer our classic costumes, and-
Dusk: The sheik is rich. Super rich.
Thorn: Anyway, you said something about undead dancing sickness? That's some serious mojo.
Luna: Only thing that can defeat it is the ultimate power chord.
Shaggy: And do you know how to play it?
Dusk: We're the Hex Girls. Magic-infused rock is how we roll.
Luna: Yay, band battle! Band battle! Can we wear our war paint? Can we? Can we? Can we?
Shaggy: Yeah. War paint. Great.
Y/N: Whatever helps you get back faster.
In Crystal Cove everyone continues to dance.
Rude Boy: We know that we will be mates forever step in with our crew, and the future's bright. We can't be beat if we stick together dance with us as we skank through the night stand up strong, put your arms around and follow along with this song. You're dead right, mate, dead right, mate, left, right, mate, yeah, that's right, mate, you're dead right, mate, dead right, mate, top night, mate, you're dead right, mate. Come on, matey!
One of the citizens falls to the ground as Dusk raises her drumsticks.
Dusk: One, two... One, two, three, four.
The Hex Girls who are now wearing face paint begins to play.
Thorn: Listen up, this won't take long, stop right there, don't try to run we're really going to give it some. So, watch out, boys, 'cause here we come. Bring it, boys!
Hex Girls: We're the good bad girls, we're the good bad girls, we're the bad good girls, don't push, or you'll run out of luck we're the good bad girls, yeah, yeah, yeah, we're the good bad girls, yeah, yeah, yeah, we're the bad good girls, yeah, yeah, yeah, don't push, or you'll run out of luck.
Rude Boy: You're dead right, mate, dead right, mate, left, right, mate, yeah, that's right, mate, you're dead right, mate.
A green skeleton skull appears and duplicates and flies through the streets infecting the citizens and they dance again.
Hex Girl: Watch out, here we come!
Multiple purple bats appear and flies freeing the citizens.
Rude Boy: Yeah, that's right, mate, you're dead right, mate.
The citizens are infected once again, and they dance.
Hex Girl: Got you on the run!
The citizens are free again.
Rude Boy: Come on, matey!
They are infected again and continue to dance.
A massive skull appears and flies towards the Hex Girl knocking them backwards.
Shaggy: Like, they're losing, Scoob! What are we going to do?
Scooby: We rock!
Y/N, Shaggy, and Scooby notice the three spare guitars and grab them.
Rude boy laughs only to see Shaggy and Y/N playing the guitars as Scooby joins and the Hex Girls get up and join them as they continue to sing.
Hex Girls: Good bad girls, we're the good bad girls, we're the bad good girls, don't push, or you'll run out of luck. We're the good bad girls, yeah, yeah, yeah, we're the good bad girls, yeah, yeah, yeah, we're the bad good girls, yeah, yeah, yeah!
A green Scooby Doo appears and flies through the streets freeing the citizens and knocks Rude Boy and the Ska-Tastics away and explodes. That's when Shaggy and Scooby begin to destroy the equipment. Y/N watches and shrugs his shoulder as he hits a speaker with the guitar as the three slam their guitars to the ground as they see the Hex Girls.
Dusk: Uh, you can stop now.
The three chuckled and soon after morning came and Rude Boy and the Ska-Tastics were handcuffed.
Fred: Now, let's see who's really behind the evil ska music. Rude Boy is actually-
Fred takes off the mask revealing an alive Rude Boy.
All: Rude Boy?
The other masks are taken off and they were all the alive singers.
Ian: You're alive! But the plane crashed thirty years ago...
Velma: Was an elaborate hoax, wasn't it, Mr. Rude Boy?
Rude Boy: Oi. You blighters got it in for me, right. But yeah, we faked the whole bloomin' thing. All I ever wanted to do was play ska and be super rich and super famous. But apparently, it just wasn't in the tarot cards, maybe the fact that we only had one song had something to do with it. So, me and me mates, the Ska-tastics here, we decided we'd fake our own deaths. Then, we could write the perfect song and return to take the music world by storm.
Martha: I don't understand, Rude Boy. Why did you wait thirty years to make a comeback?
Rude Boy: Ah, don't be such a muppet, Martha Quinn. We planned to be only gone one year, but writing the perfect song took bloomin' forever. By the time we'd cracked it, ska wasn't popular anymore. But everyone loves the undead. So, we began dressing as zombie mogs, riding our undead scooters and wearing polycarbonite-lined skull masks to hide our identity.
Velma: So, in the end, desperate for success, Rude Boy and the Ska-tastics unleashed a dancing plague on the world using an inharmonic chord with special frequencies designed to induce post-hypnotic suggestion, to sell their music.
Fred: Just as I thought, but didn't say. Dance them away, sheriff. We are done here.
The sheriff takes them away as the singers' dance into the police car.
Mayor Nettles: But what happened to Krissy Kristy and Trini Lee?
Velma: Scooby, check that coffin over there.
Scooby opens the coffin revealing the two tied up Krissy and Trini. At Shaggy's home, the gang and Hex Girls were together.
Scooby: So, uh, when are we all going on tour?
Luna: We're not.
Shaggy looks at Scooby and Y/N.
Shaggy: Like, it looks like we're going solo.
Thorn and Dusk were examining the Planispheric Disk.
Dusk: What's with the crazy music score?
Daphne: What do you mean, music score?
The Hex Girls drew a line, and it was a music score.
Velma: Those dots weren't there before. That means the Planospheric Disk has changed.
Daphne: I wish we knew how to read music.
Thorn: We do. Let's rock some harmony, Hex Girls.
The Hex Girls hum the notes, causing the disk's pieces to spin; Velma holds a lamp up, reflecting another set of coordinates onto the floor.
Velma: Another set of coordinates.
Fred: We have to go find what they lead us to.
Daphne: Maybe it's the treasure!
Y/N phone goes off and he sees it was his timer on his phone. He put it away.
Scooby: Uh, sorry, but I have somewhere else I have to be.
Y/N: Uh, yeah, me too.
Y/N and Scooby walk away. The coordinates lead Fred, Daphne, Velma, and Shaggy to the Clam Cabin, where they find Skipper Shelton wearing a peculiar helmet.
Velma: Remember, we're looking for something strange and out of the ordinary.
Skipper: Ahoy, there. How can I help you scurvy-legged land lubbers?
Daphne: Skipper Shelton that helmet you've got on. Where did you get it?
Skipper: Ahh, it be a weird thing, don't you know? I traded it with a grotesque-looking young scallywag, name of Handsome Jimmy.
All: Handsome Jimmy?
Velma: Is there something written on the inside? "S. Llave," perhaps?
Skipper looks.
Skipper: Well, bless me sand damps, there is! "S" must stand for Susan. And you must be Susan Llave! And this helmet must be yours, young fella. A strange name for a boy, though.
Velma: I'm so obviously a girl.
Fred: Who's Susan Llave?
Velma: Not Susan Llave. Segundo Llave. We've got it. This is the second key.
Daphne: But what does it all mean?
Velma: That's what we've got to find out.
Scooby visits Nova in the hospital.
Scooby: Oh, Nova. It's getting weirder and weirder. Things aren't as easy to explain anymore. It feels like something's going to happen, something bad. What do you think, Nova?
Nova flatlines.
Scooby: Nova? Nova?
Nova opens her eyes and sits up.
Nova: Nibiru. Nibiru is coming.
She then collapses again. Meanwhile, at the cemetery, Y/N is looking at his parents' grave as he kneels down and touches it. Today was the day they passed away. He was mourning when clouds rolled in, and a green aura struck the ground much to Y/N's shock. Soon after, it vanishes and that's when a zombified hand comes out of the ground startling Y/N as he crawls backwards. Three more hands emerge from the ground as two corpses crawl out. It was Y/N's parents. They crawl out of their graves horrifying Y/N. Their entire body is decomposed as maggots come out of their body. The parents stare at their son.
F/N and M/N: Nibiru. Nibiru is coming.
Suddenly their corpses turn to skeletons and fall to the ground and once it does, it turns to ash, leaving Y/N in shock and horror.