- Actor Allusion:
- Casey Kasem, the previous voice of Shaggy, provides the voice of his father, Colton Rogers.
- Matthew Lillard, who played Shaggy in the live action theatrical films, voices Shaggy starting with this series, replacing Casey Kasem.
- James Marsters playing an American character who uses a British accent.
- Clancy Brown once again voices the supernatural villain of a series, who has been manipulating the evil genius big bad to follow his will.
- This isn't the first time Patrick Warburton has played a lawman or a character with the last name Stone.
- In Episode 4, David Faustino plays a down-on-his-luck guy named Bud. Huh, where have we seen that one before?
- The mother of Velma's Stalker with a Crush Jason is played by Jessica Walter, who played one herself in Play Misty for Me.
- In episode 18, James Hong's character takes on the guise of a powerful Chinese wizard.
- Of course, the H.P. Lovecraft Expy is played by Jeffrey Combs.
- From "The Night the Clown Cried", Crybaby Clown is voiced by Mark Hamill, who has much experience with voicing clowns.
- Crybaby Clown also seems like an allusion to Hamill's role as Macendale/Hobgoblin on Spider-Man: The Animated Series, since the villain is more practical-minded than Joker, and both are shallow pretty-boys who romance the local rich girl who is fed up with her distracted ex/potential beau and turn to destructive crime waves in the name of money/fame. Both Daphne and Felicia Hardy are made to feel like fools when their date is unmasked.
- His alter-ego is voiced by his father, Matt Lanter.
- Early on in season two, Velma seems to have become pretty good friends with Hot Dog Water. It probably doesn't hurt Hot Dog Water's voice actress Linda Cardellini has a bit of a past relationship with Velma...
- Ricky Owens's teenage voice actor was Scott Menville who played Shaggy in Shaggy & Scooby-Doo Get a Clue!.
- Horatio Kharon, the dancing man in Scooby's dreams, is played by Michael J. Anderson, who played "The Man From Another Place" in another show that takes place in a small town. The characters are also rather functional and similar in design and role, down to looking almost exactly like the actor.
- In Episode 12, Harlan Ellison® spouts out a paragraph about the monster, full of "f" words (but not the F Word).
- Tim Matheson is basically voicing an adult version of Jonny Quest, to the point where the character in season two is radically redesigned from his teenage self to resemble Jonny.
- Gary Cole playing Fred's adopted father isn't the first time he's taken a job from Tim Matheson. He also became Vice President in The West Wing after Matheson's character John Hoynes had to resign in disgrace.
- In The Brady Bunch movies, Tim Matheson played a con-man that claimed to be Carol Brady's deceased first husband — her current husband being played by Gary Cole.
- In She's All That, Tim Matheson played the father of Freddie Prinze Jr.'s character. Freddie Prinze Jr. would later play as Fred in the 2002 Scooby-Doo film. (Matthew Lillard also was in She's All That and the Scooby-Doo film.)
- Mayor Jones is a high school principal in the good universe, just like Gary Cole's other role as Principal Shepherd in Family Guy.
- Becomes Hilarious in Hindsight when it turns out Principal Shepherd is divorced, and a story arc is about Brian & Stewie suspecting him of murdering his wife (he didn't). Patrick Warburton's character, Officer Swanson, is also involved in that story arc.
- Mayor Jones wears the same suit-and-tie as Harvey Birdman, another character voiced by Gary Cole. Attorney At Law also parodied other Hanna-Barbera shows, including a crossover with the original Scooby-Doo.
- In “The Creeping Creatures”, Mayor Jones answers the phone with “N’yellow?”, just like Harvey.
- For the Freak of Crystal Cove, Frank Welker uses the voice he used for the Boogieman. Whether by design or coincidence, the Freak has a few visual similarities to Boogie (such as being pale white and having horns).
- Maurice LaMarche's voice for Vincent Van Ghoul sounds like a higher-pitched version of his Brain voice, which of course is a combination of Orson Welles and Vincent Price, the latter of whom Van Ghoul is based off of.
- The Cast Showoff: Daphne gets to sing, not one, but TWO songs in the episode "In Fear Of The Phantom". Grey DeLisle knocks both right out of the park.
- Casting Gag:
- Scott Menville voiced Shaggy in Shaggy & Scooby-Doo Get a Clue!. Now he's voicing Shaggy's counterpart in the predecessor Mystery Inc., albeit the teenage version
- Baylor is a trifecta:
- First, Matt Lanter played the Edward Cullen Expy in a Twilight parody, so having him play a parody of a Twilight actor seems fitting.
- Second, Mark Hamill plays a clown when his best known voice acting role was a clown.
- Finally, Matt Lanter voiced Anakin Skywalker at one point. Mark Hamill was of course, Luke. This means Crybaby Clown is his own father.
- Hot Dog Water, a knockoff of Velma, is voiced by the actress who played her in the live-action movies, Linda Cardellini.
- Shaggy's dad, Colton Rogers, is voiced by Casey Kasem, his very first voice actor.
- Gary Cole plays a character named Mayor Fred Jones. Before that, he played Ted Jones in Pineapple Express and was a neighbor to a Jones family in The Joneses.
- Creator Backlash:
- The original creators of Scooby Doo, Where Are You! dislike the series for its depiction of the characters and its overall cynicism.
- Reportedly, Scott Innes, a voice actor for Scooby, Shaggy, and Scrappy in other works, isn't fond of Mystery Incorporated.
- Descended Creator:
- Producer Mitch Watson voices Gary's friend Ethan.
- Paul Rugg voiced a professor character in an episode he wrote.
- Executive Meddling: While nothing specific was stated, Mitch Watson said that some ideas were shot down for being too scary or weird by the "powers that be".
- Fandom Nod: In "Dance Of The Undead", when asked why the Hex Girls went back to their original outfits (resembling the ones worn in Witch's Ghost), they say that fans just preferred their original look. Some fans complained about their new look, so this is more than likely a little in-joke.
- Fan Nickname: The Nibiru Entity is actually referred to as the Evil Entity in the series proper.
- He Also Did:
- The character designer, Derrick J. Wyatt, is an alum of Teen Titans and Transformers Animated. He would do Ben 10: Omniverse after this.
- One of the directors, Victor Cook, co-produced & co-developed The Spectacular Spider Man with Greg Weisman, later becoming the supervising director for Stretch Armstrong and the Flex Fighters.
- "In Fear of the Phantom" was directed by Lauren Montgomery, who would be known for being supervising producer on The Legend of Korra and executive producer & a co-showrunner of Voltron: Legendary Defender.
- Tony Cervone and Spike Brandt were supervisor producers and directors for Duck Dodgers, direct-to-video films for this franchise as well as Tom and Jerry direct-to-video films, and The Looney Tunes Show.
- I Knew It!:
- Judy Reeves is Fred's mother, as the flashbacks in Season 1 depicted her as having a Strong Family Resemblance to Fred. Also to a lesser extent, Brad Chiles is Fred's real father. The Season 1 finale would confirm this.
- Cassidy Williams and Angel Dynamite having some sort of relation, possibly because they're the same person. This was confirmed near the end of Season 1.
- Mayor Jones being divorced from Fred's mother (or more accurately, she left him). Confirmed in "A Haunting In Crystal Cove", or at least that's what his cover story was.
- Mayor Jones is involved in the show's Myth Arc via the disappearance of the original Mystery Incorporated, and is not a trustworthy figure.
- Betrayal broke apart the original Mystery Incorporated because of Pericles.
- Jossed: Many people liked to believe that Cassidy survived the underwater explosion, and that she was just hiding. This is not the case, as she does not reappear until the timeline had been reset.
- Non-Singing Voice: Averted with the Hex Girls and Daphne. All of the actresses performed the songs played within the show.
- The Other Darrin:
- Casey Kasem retired from the role of Shaggy, and handed the role over to Matthew Lillard. This is also a role reprisal from the theatrical live action films.
- Lewis Black voices Mr. E, but one episode has him voiced by Jeff Bennett.
- Due to Vincent Price's death, Maurice LaMarche voices Vincent Van Ghoul.
- Gary, Ethan's friend, was voiced by Tony Cervone in season 1 and by Jeff Bennett in season 2.
- Screwed by the Network: Despite universal praise the series was screwed in Season 2 where there would often be months between new episodes and no news of when new episodes would come out. It was easier to find the episodes online rather than TV. Luckily however, they managed to wrap up the series at the end instead of outright canceling it like many other shows that have been screwed.
- Series Hiatus: Has had three. The series has now ended.
- Talking to Himself: Frank Welker voices Fred, Daphne's father, and Scooby-Doo.
- Voices in One Room: As explained here
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- What Could Have Been:
- The final show was always meant to be a two-season series, but Word of God says that they actually did consider a Season 3, which would have had a new Myth Arc and expanded on the Stealth Prequel aspect.
- According to early press releases, the story would have been somewhat different, as the gang is only visiting Crystal Cove instead of having grown up there:
The kids from Mystery, Inc. arrive in the village of Crystal Cove, a small town known for its many ghosts and ghoulies. Fred and Velma are determined to debunk the area's many paranormal phenomena.But it turns out the locals are none too eager to have their mysteries quashed! Will the gang's head for logic prevail over centuries of local legend?- The Freak was originally named "The Fiend".
- Pericles was considered wearing a mask based off of Hannibal's.
- Judging by the credits of "Mystery Solvers Club State Finals", the Black Knight from the very first episode of Scooby-Doo, Where Are You! was supposed to appear, possibly voiced by Gary Cole. He is also credited with reprising his role as Mayor Jones, who doesn't appear in this episode either besides a name drop.
- The final show was always meant to be a two-season series, but Word of God says that they actually did consider a Season 3
- Word of God: You could ask Tony Cervone, one of the writers, questions about the show on Twitter, but his original account has since been deleted as of early 2018.
- Crystal Cove is indeed in California.
- Nan Blake suffers from multiple Ambiguous Disorders.
- Mayor Jones is in his fifties, Sheriff Stone is in his "fifties-ish", and Mayor Nettles is in her mid-thirties.
- Mayor Jones wasn't lying in "All Fear the Freak" when he said that he loved Fred. This later became clear at the end of Season 2.
- Mayor Jones was the one that bought Fred his teddy bear in "The Night the Clown Cried", Mr. Trapples.
- Mayor Jones was from elsewhere in California.
- Cassidy was indeed killed at the end of "The Midnight Zone".
- Mayor Jones would've ended up worse than Brad and Judy without Fred in his life as a Morality Pet.
- The gang took time to say goodbye to their friends and family before leaving Crystal Cove at the end of the series.
- Mitch Watson implies in a post-series interview that the show is actually a Stealth Prequel to a Broad Strokes of the original canon rather than the original canon straight-up.
