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Needed: Synopsis is missing real opening and ending.

The Diabolical Disc Demon is the first of three segments of Scooby's All-Stars. It was later repackaged as the eleventh episode of the third season of The Scooby-Doo Show, and the thirty-fifth episode overall in the series.


The gang go to Decade Records recording studio to see a live recording from their friend, Jimmy Lewis, but the building is haunted by the Phantom, who is trying to find a song by a missing writer, and will stop at nothing until he gets it.


The gang is headed to Decade Records to watch a live recording of a famous friend of theirs, Jimmy Lewis. Upon arrival at the studio, they are greeted by an unwelcoming security guard named Joe. Jimmy lets the gang in, letting the guard know that they are friends of his. Jimmy tells the gang that one of his songwriters, Tony Synes, has disappeared, and left behind a strange piece of music that Jimmy tells the gang he will be performing tonight.

Jimmy introduces the gang to his pianist and arranger, Ian Barkin, Ace Decade, the studio owner's nephew, and the recording engineer, Brick Tyler. Ian begins to play the song written by Tony before he disappeared, and suddenly the recording equipment begins to malfunction. The gang then hear about a phantom that is haunting the studio, much to Scooby and Shaggy's chagrin. Jimmy explains the phantom is the ghost of a musician seeking vengeance against those who ruined his career. Jimmy then takes Fred, Daphne, and Velma on a tour of the studio, and Shaggy and Scooby stay behind to play around with the equipment.

The Phantom then appears, who looks like a glam rock musician, and chases Shaggy and Scooby, stealing the piece of music that Tony Synes wrote before he went missing. Shaggy and Scooby find the gang and Jimmy and tell them of their encounter with the Phantom. Jimmy and the gang return to the studio to look for the Phantom, but he is gone, along with the music. Scooby and Shaggy go to Jimmy's dressing room to retrieve a copy of the music, and have another run-in with the Phantom, who tries to take the copy. The Phantom chases Shaggy and Scooby, going after the music, and Scooby and Shaggy manage to escape with the music. They meet up with the gang and tell them about the Phantom.

Suddenly, the Phantom comes over the Intercom and threatens the gang. The gang decide to go search the offices for the phantom and Shaggy and Scooby go to the cafeteria to chow down. Velma, Fred, and Daphne find the source of the voice in Ace Decade's office, it was only a tape recording. Ace Decade tells the gang he has no idea how it got in there, and no one else has a key but himself. Scoob and Shag go to the cafeteria to eat, and think they see the Phantom in a storage closet, locking him in. They run to tell the gang, but are caught and thrown out by Joe, the guard.

Back in the studio, the recording session is cancelled and postponed until tomorrow. Scooby and Shaggy devise a way to get back into the studio, and in the process, find hundreds of Jimmy Lewis records in the trash outside. Meanwhile, Fred, Daphne, Velma, and Jimmy think of what could be so special about the song that Tony Symes wrote. Scooby and Shaggy get back inside and tell the gang about the clue in the trash, and then the Phantom appears and tries to take the music, but the gang stops him and the Phantom chases them, trying to get the music, and in the process, falls into his own trap.

The Phantom is unmasked as Ace Decade. He was stealing records from his uncle's studio and selling them for his own profit. The tape recording in his office was a ploy to make it seem like he was being framed. The biggest clue was the song that Tony Synes wrote and left when he disappeared. The notes in the first three bars read ACEDECADE pointing an accusing finger straight at Ace. Once Ace heard the song, he realized what Tony did and faked the malfunction to stop the session. The Phantom was a cover for the operation.

Tony Synes is revealed to be the person locked in the storage closet that Shaggy and Scooby thought to be the Phantom.


Main characters:

Supporting characters:


Other characters:

  • Mr. Decade (only time mentioned)
  • Cat (single appearance)(no lines)





Suspect Motive/reason
Joe He was surly and unpredictable.
Ian Barkin He noted the oddness in Tony Symes's song.
Ace Decade He is the only one who had a key to his office.
Brick Tyler He could have sabotaged the recording equipment.


Culprit Motive/reason
Ace Decade as the Phantom To get the song, which exposed his guilt.


Don Messick Scooby-Doo
Casey Kasem Shaggy Rogers
Frank Welker Fred Jones
Heather North Daphne Blake
Pat Stevens Velma Dinkley
Michael Bell Ace Decade
Alan Oppenheimer Joe
Wayne Morton Jimmy Lewis


Animation mistakes and/or technical glitches

  • None known.

Inconsistencies/continuity errors and/or goofs/oddities

  • The Phantom seems to be following Shaggy and Scooby or they coincidentally wind up in all the same places as the Phantom. Fred, Daphne, and Velma do not encounter him until the very end of the episode aside from hearing his voice through the loudspeakers.
  • The idea that the song is a clue narrows the suspects down to one as only one of them can have his name spelled out with the letters A-G.

Home media


External links

  • TBA

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Season 3
Scooby's Chinese Fortune Kooky Caper
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