Scooby-Doo! Mystery Incorporated tells the early story of Scoob and the gang solving mysteries in their hometown of Crystal Cove. The series was like none that came before, occasionally featuring real monsters and other supernatural elements and giving Fred, Daphne, Velma and Shaggy more character development and personality than they had in previous incarnations.

While the show kept the "monster of the week" format, it had an overarching story involving demons and the original gang of mystery solvers who vanish without a trace. The series also featured numerous callbacks and references to previous works in the Scooby-Doo franchise. From guest appearances by classic monsters to cameos from different friends and allies, here's a list of all the times Scooby-Doo! Mystery Incorporated referenced other projects in the franchise.

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Crystal Cove Museum's Costumes

The Crystal Cove Spook Museum is a tourist attraction owned by Velma Dinkley's parents. In the show's first episode, Velma gives an unenthusiastic tour of the museum and shows off some of the "monsters" she and the gang unmasked from the 1969 animated series Scooby-Doo, Where Are You!, including Captain Cutler's Ghost, the Miner '49er, Charlie the Haunted Robot and the Space Kook. Later in the series, Fred and Daphne stumble across a wax figurine of Scrappy-Doo, Scoob's ill-received cousin, in the museum, but they decline to discuss his falling out with the rest of the gang, which may be a callback to Scrappy's turn to villainy in the 2002 live-action Scooby-Doo.

Vincent Van Ghoul 

An image of Vincent Van Ghoul from the series, Mystery Incorporated

Vincent Van Ghoul, a tribute to horror movie star Vincent Price, made his debut in 1985's The 13 Ghosts of Scooby-Doo and is a warlock with extensive knowledge of the supernatural who joins forces with Scoob, Shaggy and Daphne to track down 13 escaped ghosts. In Scooby-Doo! Mystery Incorporated, he's a famed B-movie star who's films Shaggy and Scooby watch several times throughout the series. The two eventually meet their idol in the nineteenth episode of the first season, "Nightfright," in which they must save Van Ghoul from a jealous rival disguised as a demon.

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The Creeper

Besides appearing as an exhibit in the Crystal Cove Spook Museum, the Creeper, a disguise worn by bank manager Deacon Carlswell, appears in an unmasking flashback in the Season 1 episode "The Legend of Alice May," in which high school student Alice May uses his costume as the inspiration of her Ghost Girl costume. The episode even features a flashback sequence to when Scooby catches the Creeper and unmasks him after an extended chase sequence.

The Hex Girls

An image of the Hex Girls from the series, Mystery Incorporated

While they only appear in a few episodes throughout the series' two-season run, the Hex Girls' presence is heavily felt. Velma has a poster of the famous trio, who made their debut in the 1999 direct-to-video animated Scooby-Doo: The Witch's Ghost, and several episodes feature discography by the band. In the Season 1 episode "In Fear of the Phantom," the Hex Girls are threatened by a phantom, and Daphne disguises herself as a member of the band to solve the mystery. The group also appears in the Season 2 episode "Dance of the Undead," taking part in a battle of the bands.

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"Danger-Prone Daphne"

Daphne screams in Mystery Incorporated cartoon

Daphne Blake earned the nickname "Danger-Prone Daphne" in Scooby-Doo, Where Are You! for her tendency to get captured by the episode's villain or fall through trap doors. She's certainly become more self-reliant as the franchise progressed, but occasionally the other Mystery Inc. members teasingly refer to her by the damsel in distress nickname. In Season 1, Episode 8, "The Grasp of the Gnome," Velma calls Daphne by the nickname when the gang attends a renaissance fair and encounters a sinister Gnome. Daphne leans against a tree while hunting for the Gnome and activates a trap door, tumbling down into the darkness below.

The Wax Phantom

In the Scooby-Doo, Where Are You! episode "Don't Fool with a Phantom," the gang are invited as contestants on a Dance Game Show, but the event is attacked by the Wax Phantom, a glow-in-the-dark disguise worn by the disgruntled TV station manager, Roger Stevens. In Mystery Incorporated's "Howl of the Fright Hound," the Wax Phantom is mentioned by Velma's mother during the Crystal Cove haunted bus tour.

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Cass Elliot

The seventh episode of Season 2 of the New Scooby-Doo Movies, "The Haunted Candy Factory," features none other than Cass Elliot, a member of the famed band The Mamas and the Papas. Sadly, the singer passed away in 1974, nine months after the episode aired. Scooby-Doo: Mystery Incorporated pays tribute by featuring a Crystal Cove citizen and lookalike to the singer who often finds herself in the middle of the town's spooky happenings.

Golden Years of Hanna-Barbera

Season 1, Episode 14, "Mystery Solvers Club State Finals," features Scoob joining forces with the likes of Speedy Buggy, Jabberjaw, Mudsy Muddlemore and Captain Caveman to save their friends from the Lord Infernicus, a disguise worn by the Funky Phantom who was tired of being a sidekick. However, it's revealed that the episode was a fever dream as Scooby had a cold right before the actual Mystery Solvers Club State Finals. Nevertheless, it was cool to see a gathering of some of Hanna-Barbera's most iconic crime-solvers who all followed the same basic formula of unmasking criminals made popular by Scooby-Doo, Where Are You!

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"Night Terrors"

Season 2, Episode 10, "Night Terrors,"  features two callbacks to classic episodes of Scooby-Doo, Where Are You!. The episode follows the gang as they investigate a creepy mansion after a landslide forces them to seek shelter.  Besides being a cheeky reference to The Shining, the snowsuits they wear similar to the ones from the episode "The Snow Ghost," and a family terrorized in the opening scene is the same family vacationing in the episode "The Creeping Creatures."

"The Wrath of Krampus"

Season 2's "The Wrath of Krampus" features a villain who attacks "bad kids," prompting the gang to join forces with some criminals they've unmasked in the past. The gang also utilizes Charlie the Robot, who debuted in the Scooby-Doo, Where Are You! Season 1, as a distraction against Krampus. Other villains from across the franchise make guest appearances, including the Luna Ghost, a villain from both the classic cartoon and the 2004 live-action Scooby-Doo 2, and the Giggling Green Ghost from the Scooby-Doo, Where Are You! episode "A Night of Fright is No Delight."

The Blue Falcon & Dynomutt

When a robot dragon attacks a company called Quest Industries in the Season 2 episode "Heart of Darkness,"  the gang teams up with none other than the Blue Falcon and Dynomutt, who were featured alongside Scooby-Doo in the cartoon television series The Scooby-Doo/Dynomutt Hour, which ran from 1976-1977. Scooby-Doo and the gang made various appearances in the series and the Batman-esque went on to appear in the direct-to-DVD film Scooby-Doo: The Mask of the Blue Falcon. 

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