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Nightmare Bitters as she is first seen.

Nightmare Bitters is the Nightmare doppelganger of Ms. Bitters, and as such, she made her only appearance in the "Halloween Spectacular of Spooky Doom". She appears to be the ruler of the Halloweenies and was the main antagonist of the special.

Since the Nightmare Realm is located within Dib's mind, then Nightmare Bitters could be viewed as an exaggerated negative representation of how Dib sees his mean-spirited teacher at her worst (which is always), although interestingly and ironically she is a bit less cruel than the real Ms. Bitters.


Nightmare Bitters owns the Nightmare Skool and is a commander of the Halloweenies. The nightmare version of Ms. Bitters leads the operation to get to the real world. She attempts to achieve this by using a device to open up a portal through Dib's head as his mind is the source of her dimension.

When Zim rescues Dib, she became so enraged that she transforms into a larger creature. She eventually makes it to the real world, but becomes so horrified by the children and a candy-bloated GIR that she returns to her dimension.


Nightmare Bitters shrieking in rage.

In contrast to Ms. Bitters who is devoid of any positive emotion, Nightmare Bitters is actually somewhat more affable and humorous, she can also be absent minded at times since she has been known to not think ahead like giving an inspirational speech to her army and then bitterly kicking herself over it.

She has a bad habit of banishing her underlings to the "Realm of Eternal Screaming and Restlessness" even for things that were out of their control, thus still keeping the cruel behavior like her counterpart. Despite this, she tends to be more affable towards them, even when she banishes them.

Surprisingly Nightmare Bitters has the ability to show fear unlike her counterpart who gives fear, as she was seen scared and disturbed when she forces her way through the portal in Dib's head, victoriously thinking that there's a new world for her to destroy only to turn to horror as she sees the skoolchildren's in their costumes, thinking of them as creatures far more horrifying and disgusting than the ones in the Nightmare Realm, the final coup de grace was when she noticed GIR, who has become morbidly obese from eating all the Halloween candy, making scream in terror as she returned home, weeping sounds could also be heard as she closed the portal for good.


Nightmare Bitters in her monstrous insect-like form.

Nightmare Bitters is a large, grotesque, bowlegged creature with a hunch. She wears glasses with a purple tint, and has a multitude of long, striped tentacles protruding from her back.

After Zim rescued Dib in the Nightmare Mech, she demonstrated her capability to transform into a giant insect-like creature and gave chase to the pair. Nightmare Bitters wears a ragged purple dress with vertical white letters spelling the word B A D.

Facts of Doom

  • Nightmare Bitters was not voiced by the late Lucille Bliss but rather by Rodger Bumpass (who voices Professor Membrane), making her one of the two female character in the show voiced by a man, the other being Darlene O´Booboo who was voiced by Wally Wingert.
    • It's unknown why Lucille Bliss didn't voice Nightmare Bitters, as the rest of the cast did voice their real life and nightmare realm counterparts.
  • Zim seemed to be horrified that there is another version of Ms. Bitters when they met.
  • Her legs seem very similar to the legs of Johnny C. Her back tentacles also bare a resemblance to the stripes on his sleeves.