Heart of Evil is the fourteenth episode of the second season of Scooby-Doo! Mystery Incorporated, and the fortieth overall.


When a humanoid robotic dragon comes to Crystal Cove, two super-hero vigilantes follow suit.


Five years prior, Radley Crown is working as a guard at Quest Labs when a dragon-like robot attacks before being beaten by Race Bannon. Dr. Quest then agrees to help save his dog's life.

The gang visits Fred and Nova at their new van/home before going to City Hall. Velma shows them a device she made to try and decipher the Disk. They're surprised by a noise in the records room. They go there to find Blue Falcon and Dynomutt fighting the same robot from five years prior. After the robot runs away, the gang talks to Blue Falcon about the dragon robot before agreeing to help him track it down.

Velma shows the Falcon how she got the records from the city hall. Soon after, Blue Falcon and Dynomutt launch an all-out assault on Destroido headquarters. Mr. E confronts them and the gang about why they are attacking his facility in such an obvious way. Blue Falcon threatens Mr. E, but is interrupted when a security alarm goes off revealing that the Dragon has attacked Destroido as well. The Dragon is revealed to be controlled by a man named Zin, who then tells the Dragon to abduct Blue Falcon and his dog for the Quest X Power Source. However, the Dragon grabs Scooby by mistake before flying away.

Zin then starts interrogating Falcon, but fails when he realizes that he grabbed the wrong dog. The gang asks E about the power source, before going to the island in Blue Falcon's flying car. He is getting ready to throw Scooby and Falcon into the dungeon when he sees the gang arriving. He tries to destroy them but misses and they invade his fortress and beat up all of his security guards. After the fight, Falcon then reveals that Dynomutt was powered with the Quest-X power cell. Zin reveals that his attempts at stealing it were to rescue his daughter from the Dragon battle suit. Dynomutt uses a power cable to jump start the Dragon suit and remove Zin's daughter. Zin talks about how he appreciates their help, before setting the island to self destruct and leaving them to die. The gang floats off into the moonlight while Scooby and Falcon discuss whether he should devote the rest of his life to hunting down Zin.


Main characters:

Supporting characters:

  • Radley Crown (only appearance)(flashback only)
  • Race Bannon (first full appearance)(flashback only)(final appearance)
  • Dr. Benton Quest (first full appearance)(flashback only)(final appearance)
  • Blue Falcon (only appearance)(Radley Crown's disguise)
  • Reggie (only appearance)(no lines)(near fatally wounded)
  • Dynomutt (only appearance)(cybernetically enhanced Reggie)


  • Dragon (only appearance)(no lines)(main story and flashback)(Jenny Zin's disguise)
  • Dr. Zin (only appearance)
  • Bobo (only appearance)
  • Destroido guards (only appearance)(miscellaneous speaking)
  • Dr. Zin's soldiers (only appearance)(miscellaneous speaking)
  • Dr. Zin's scientists (only appearance)(miscellaneous speaking)
  • Jenny Zin (only appearance)(main story and flashback)
  • Mr. E

Other characters:

  • Bandit (mentioned)
  • Old clerk (no lines)





Frank Welker Scooby-Doo
Fred Jones, Jr.
Matthew Lillard Shaggy Rogers
Grey DeLisle Daphne Blake
Jenny Zin
Mindy Cohn Velma Dinkley
Lewis Black Mr. E
Eric Bauza Dr. Benton Quest
Old clerk
Dr. Zin
Troy Baker Blue Falcon
Radley Crown
Christopher Smith Race Bannon



Cultural references

  • Dr. Zin is actually an enemy of the Johnny Quest TV series.
  • Blue Falcon and Dynomutt are main characters in Hanna-Barbera's Dynomutt, Dog Wonder, which was originally a part of The Scooby-Doo/Dynomutt Hour.
  • While Dynomutt retains his personality from the original Dynomutt series, the Blue Falcon is portrayed as a gritty and violent vigilante, like the Batman from the comic book, The Dark Knight Returns.
    • Blue Falcon's line about seventeen ways to incapacitate them, all of which hurt, parodies a line from the The Dark Knight Returns, "There are seven working defenses from this position: three of them disarm with minimal contact, three of them kill, one of them... hurts."
  • The origin of Dynomutt as a cyborg because of a medical emergency is like what happened to Steve Austin in the Six Million Dollar Man TV series.
  • Bobo is based on Simon 1, a henchman of Dr. Zin, from the Jonny Quest episode The Fraudulent Volcano.

Inconsistencies/continuity errors and/or goofs/oddities

  • Despite what happened in the last episode, Nova is mysteriously absent in this episode and it's unclear where she's been placed. It's possible she was given to Fred for the time being as they both move into one of the spare twenty bedrooms of Daphne's mansion in the next episode, which she offers in this one.

In other languages

Language Name Meaning
French Le Coeur du Mal Heart of Evil
Greek Στην Καρδιά του Κακού In the Heart of Evil
Hungarian A démon lelke The Spirit of the Demon
Italian Quest X Quest X
Spanish (Latin America) Corazón de Maldad Heart of Evil

Home media


Velma: Hmmm. I can't say I totally endorse the concept of a masked vigilante.
Fred: Velma, he's a superhero with a belt fill of traps!

Dr. Zin: But you said you would do anything. Sacrifice anything to save your dog!
Blue Falcon: I would. But that's not my dog.

External links

  • TBA

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Wrath of the Krampus Scooby-Doo! Mystery Incorporated
Season 2
Theater of Doom