Dimension Doom is the thirty third episode of ThunderCats (original series).


Mumm-Ra gains possession of Wizz-Ra's mind-controlling helmet and uses it to turn the ThunderCats into his slaves. Only Cheetara and Snarf are left and they team up with Wizz-Ra to regain the helmet before it is too late.


An apparition of Wizz-Ra, an ancient Egyptian sorcerer, appears in the mirror in Cheetara's room, waking her from her sleep. While initially wanting to tell the rest of the ThunderCats about this strange occurrence, Cheetara decides against it, fearing that they might not believe her.

Meanwhile, Mumm-Ra watches Cheetara from his cauldron inside the Black Pyramid and explains to Slithe that Wizz-Ra possesses the Enchanted Golden Helmet of Pharnoor. The helmet gives its wearer the power to control minds. He recalls how many centuries ago he had tricked Wizz-Ra into getting banished and imprisoned in the Seventh Dimension for all eternity. However, once every seven thousand years, Wizz-Ra is able to return to Third Earth for one single day via a portal which coincidentally happens to be on the exact same spot as the mirror in Cheetara's room.

Mumm-Ra then brings the Fatatah Cheetah statue in his pyramid to life using his powers. He instructs the feline to bring him the enchanted helmet. The cheetah speeds to the Cats Lair and, avoiding detection, climbs into Cheetara's room and enters her body. At that moment, Wizz-Ra emerges from the mirror and the Fatatah Cheetah lunges on him. The cheetah then grabs his helmet and takes it to Mumm-Ra.

Inside Cats Lair, Lion-O and Snarf are unable to wake Cheetara from her sleeping trance. Wizz-Ra explains that she is under Mumm-Ra's power and only if he had his helmet could he break her trance. Thus the trio immediately head to the Black Pyramid. Once there, Mumm-Ra uses the enchanted helmet on Lion-O and starts taking control of his mind. Lion-O uses every ounce of his strength to summon the other ThunderCats before completely falling under Mumm-Ra's control.

Mumm-Ra orders the entranced Lion-O to throw the Sword of Omens into the Desert of Sinking Sands where it disappears without a trace. Lion-O then attacks Wizz-Ra but the sorcerer uses his magic power to stop Lion-O in his tracks. Shortly after, Panthro, Tygra, Wilykit and Wilykat arrive and they all fall victim to Mumm-Ra's mind control. Like Lion-O, they too attack Wizz-Ra and again he uses his magic to subdue them. After expending so much of his power, the weakened Wizz-Ra and Snarf retreat back to Cats Lair.

Outside the lair, Wizz-Ra and Snarf encounter Cheetara, who has broken free of Mumm-Ra's control. The three then head back to the Black Pyramid and sneak inside it undetected. While Mumm-Ra and Slithe are gloating over their success, Cheetara quietly moves the Vulture King statue so that the sun's beam coming from the roof hits its left eye. This fools Mumm-Ra into thinking that the day is over and Wizz-Ra has returned to his dimensional prison and so he removes the helmet. Snarf quickly grabs the helmet and gives it to Wizz-Ra who uses it to free the ThunderCats from Mumm-Ra's control and then blasts Mumm-Ra with his magic, causing the mummy to retreat into his sarcophagus.

With the day almost over, Cheetara helps Wizz-Ra to get back to the portal before time runs out for him. Wizz-Ra then thanks Cheetara and bids her farewell before entering the mirror and returning to his dimension. Lion-O calls the Sword of Omens and it emerges from the sands and flies into his hand.


Cheetara: "Maybe if I had trusted you more and told you about WIzz-Ra, all this wouldn't have happened".
Lion-O: "That's in the past Cheetara. But in the future, we must hold nothing back from each other if we are going to remain a team".




  • In this episode, we learn the name of one of the four statues in Mumm-Ra's tomb chamber. The vulture-like statue is known as the Vulture King.
  • This episode is unusual for Mumm-Ra in that during it he never transforms into his Ever-Living form. This would be a rare occurrence throughout the series, with Mumm-Ra's transformation usually taking place whenever he would appear in an episode. Although of course in the case of this episode it could be argued that he had no need to transform given the enhancement to his powers granted by Wizz-Ra's enchanted helmet. However, Mumm-ra is shown in his ever-living form in the flashback scene in which he is battling Wizz-Ra.
  • The appearance of the Sphinx in this episode further corroborates the theory that Third Earth is a future version of our present Earth.
  • The energy bolt that Mumm-Ra fires at the Sphinx is apparently an explanation for the missing nose on the real Sphinx of Giza which is located in present-day Egypt.
Dimension Doom trivia1.jpg

Animation Mistakes and/or Technical Glitches

  • When Wizz-Ra appears in Cheetara's mirror, she is sitting up in her bed but when Wizz-Ra disappears, Cheetara's reflection in the mirror shows her sleeping.
Dimension Doom error1.jpg

  • When Mumm-Ra orders the Fatatah Cheetah to bring him the enchanted helmet, for a brief moment all the shadows on his cape disappear.
Dimension Doom error2.jpg

Inconsistencies/Continuity Errors and/or Goofs/Oddities

  • When Wizz-Ra releases the ThunderCats from Mumm-Ra's mind-controlling spell at the end of this episode, amongst their confused chatter Snarf's voice can clearly be heard saying "I must have been asleep", despite the fact that Snarf was not one of the ThunderCats that Mumm-Ra had enslaved.
  • While Lion-O, Snarf and Wizz-Ra are at Mumm-ra's pyramid, the remaining ThunderCats engage in their normal daily routines without noticing that Lion-O, Snarf and Cheetara are missing.


Slithe: What are you babbling about, my revolting comrade in evil?

Mumm-Ra: Ancient Spirits of Evil, turn stone into flesh, blood, sinew and claw

Slithe: But this Wizz-Ra, he has power too. He will use it to regain the helmet.
Mumm-ra: He only has one single day to even try, your lizard-ness.

Wizz-Ra: I am no enemy! While you delay me here, ultimate power falls into the hands of evil Mumm-Ra

Lion-O, Panthro, Tygra, Wilykit, Wilykat: Only Mumm-Ra commands us!

Cheetara: Will I see you again, wizard?
Wizz-Ra: Only in your dreams, beautiful Cheetara. Only in your dreams.


Enchanted Golden Helmet of PharnoorDesert of Sinking Sands


Episode Navigation

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