The new Marvel Cinematic Universe (MCU) series The Vision to Disney+ in a world that looks just like the sitcoms of years past. However, along with the two former Avengers , there are also kooky neighbors, including a next-door neighbor, Agnes.

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Rumors prove true as Agnes is none other than Marvel Comics witch Agatha Harkness. While Agatha used to appear as an old woman in the comics, more recent appearances have her in a younger body once again, making her youthful appearance despite her age in WandaVision make perfect sense. Just who is Agatha Harkness? Though there are differences in the MCU's adaptation, the comic book backstory for the character can provide some interesting information for fans.

Updated on May 30th, 2021 by Amanda Bruce: Fans can't get enough of Kathryn Hahn's portrayal of Agatha Harkness in WandaVision. Her sitcom performances as nosy neighbor Agnes through Wanda's decades of television are entertaining, but she also makes a compelling villain in her quest for power and her fascination with Wanda. The relationship between Wanda and Agnes is very different in the comics though, and plenty of fans might still wonder if some of her comic book stories might provide clues as to where she could go next in the MCU.

Agatha Is Over 12,500 Years Old

Agatha Harkness uses her magic on the Silver Surfer

Agatha Harkness is actually well over 12,500 years old. While her first appearance came in 1970's Fantastic Four #94 by Stan Lee, Jack Kirby, Joe Sinnott & Sam Rosen, this part of her past played out in 1998's Silver Surfer #135 by J.M. DeMatteis, Tom Grummett, Matt Ryan, Tom Smith & John Costanza. In that issue, it was revealed that she was old enough to 500 years before Atlantis sunk, which was 10,500 BC in Marvel Comics.

Kathryn Hahn Sang "Agatha All Along"

WandaVision Agatha All Along color featured

When Agnes is revealed as Agatha Harkness in WandaVision, the reveal is done in grand television fashion. Every moment Agatha manipulated the events of Wanda's pretend sitcom world is shown, but Agatha even gets her own theme song.

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The catchy tune, called "Agatha All Along," became the internet's favorite theme pretty quickly. Part of its charm might be in its delivery itself since Agatha sings it. Kathryn Hahn performed the lead vocals for it, and in fact, its that she would have been "so angry" if she didn't get to be the one to do it.

Harkness Betrayed Her Own Kind In New Salem

Agatha Harkness at Salem in the comics

Agatha Harkness was a witch, and she did a lot to ensure her own survival. This came to be very important when she lived in New Salem, where she met up with centuries-old witches and ed up with them. Over time, Agatha became the grande dame of this group and eventually turned over various witches to the witch-killing authorities. She did this undercover, while her main goal was to rid New Salem of the weaker witches to make her coven even stronger. Is Agatha Harkness evil? Not necessarily. She operates in a lot of grey areas in the comics, doing just as much good as she does bad.

She Was A Nanny For The Fantastic Four

Agatha Harkness watches Franklin Richards while Sue Storm is invisible

Eventually, Agatha Harkness became a governess for children in need, although, by the time the Marvel Comics world met its first superheroes, she had long-since retired. This all changed when the Fantastic Four put out a search for a nanny for Franklin Richards. When she realized that Franklin could have major powers, she took the job and helped the child when he began developing those powers. She also grew close to the Fantastic Four and helped them on various missions.

Agatha Is A Powerful Witch

Agatha Harkness uses her magic on The Thing and the Human Torch

Agatha Harkness hid her powers for a long time, but eventually, she revealed to the Fantastic Four that she was a witch. Not only was Agatha a witch, but she was a very powerful sorcerer, one of the strongest known at the time.

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Through the years, Agatha Harkness had proven to be a powerful ally when the Fantastic Four, and later the Avengers, needed her help. While she cannot fight, her powers as a witch have been invaluable, with her spell casting, telepathy, astral projection, and energy bolts that cause great damage.

Agatha Harkness Can Manipulate Other Dimensions

Agatha Harkness makes an entrance in Avengers West Coast comics.

As the MCU begins to explore the multiverse, the audience is curious about just what multiple timelines and dimensions could mean for the on-screen universe. Agatha Harkness knows a thing or two about that in the comics. She's able to literally put objects - and even whole cities - into other dimensions. It's a skill only a few witches master as it's more likely to see dimension-hopping as a superhero, not magical, ability.

Her Son Is Nicholas Scratch

Nicholas Scratch and Agatha Harkness appear in Marvel Comics.

One of the Fantastic Four's earliest foes was a powerful sorcerer. His first appearance came in 1977's Fantastic Four #185. He arrived in New Salem and put Agatha on trial for possibly betraying the community. It turned out that Nicholas was her son, and when he lured the Fantastic Four there, he lost their . Over time, he returned repeatedly and was eventually defeated and imprisoned, Agatha denouncing him as her son.

Agatha Made Scarlet Witch's Children Disappear

Agatha Harkness and Scarlet Witch

Over time, the Fantastic Four no longer needed Agatha Harkness to serve as Franklin's nanny, and she began working with the Scarlet Witch. When Vision and Scarlet Witch had their twins, Agatha became their nanny and watched over the two children. Agatha Harkness and Mephisto played a role in their birth to begin with Sadly, Wanda created her children using her magic, using fragments of Mephisto's soul, and Agatha knew it. In West Coast Avengers #52 by John Byrne, Mike Machian, Bon Sharen & Bill Oakley, the children ended up taken away and Agatha removed their memories from Wanda's mind.

Agatha Became Scarlet Witch's Primary Teacher

Agatha Harkness teaching Scarlet Witch

After the loss of her children, Agatha Harkness worked to help Wanda control her chaos magic better. Agatha, and the Avengers themselves, knew that Scarlet Witch had dangerously strong powers and needed to learn how to control them better, and that is where Agatha came into the picture.

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Doctor Strange mentioned he offered to help Wanda, but her Avengers duties always came first. Agatha was able to help Wanda become stronger, which even allowed the Scarlet Witch to resurrect Wonder Man. However, she never learned to use the powers responsibly.

Scarlet Witch Murdered Agatha Harkness

Scarlet Witch kills Agatha Harkness

The biggest downfall for Scarlet Witch came when she created a brand-new world in House of M and then became a villain for life in the eyes of the X-Men during M-Day. However, she soon lost even the Avengers' when she ed that her twins existed and were taken from her. When she learned of Agatha's role in the deception, Wanda murdered her and then attacked the Avengers in the "Avengers Disassembled" storyline.