Like a lot of characters in WandaVision, Agatha Harkness was created by Jack Kirby, and his original design for her was much different from what ended up on the printed page. One of the last characters that Jack created for Marvel during his tenure on Fantastic Four, Agatha Harkness captured readers' imaginations in a debut straight out of a horror movie. Although her debut has the hallmarks of a classic Jack Kirby horror comic, some of his best ideas for the issue were unused by editor/writer Stan Lee. The only clues are surviving original pencils, and script notes from Jack, but the reason Agatha's design was changed is debated to this day.

In the Marvel Universe, Agatha Harkness is one of the original Salem Witches, and she made her debut in the pages of Fantastic Four #94, with art and story by Jack Kirby, and dialogue by Stan Lee. Fantastic Four #94 is the first comic that reveals the name of Reed Richards and Sue Storm's child, Franklin Richards. The story revolves around their need to find a "child-rearing specialist" to take care of Franklin should they have to fight criminals or stop a disaster. This leads them to Agatha, a mysterious old woman who has come out of retirement as a "world-famous child-rearing specialist" because of the prestige of caring for the son of the Fantastic Four. Agatha's house is attacked by the Frightful Four, but Agatha uses magic to defend the house, proving to Reed and Sue that she is more than capable of taking care of their son.

Related: How Jack Kirby Influenced the MCU and DCEU

The story that saw print in Fantastic Four #94 was largely unchanged from what the legendary Jack Kirby wrote and drew, but with some key changes. According to Kirby historian John Morrow's book Stuf' Said, the script notes on Jack's original pages referred to Agatha as "Aunty" throughout the script, rather than a "child-rearing specialist," with one line of dialogue implying Agatha was Sue's half aunt. While there is much speculation, the likely answer to Agatha's appearance on the original pencil Xeroxes compared to the printed page has to do with Lee's changing Agatha to a nanny. Kirby likely changed Agatha to an older woman so as not to draw comparisons to Mary Poppins. Whether the original design was inspired by Poppins is unknown, but perhaps Lee's change of Agatha to a nanny was one similarity too many.

Released within a year of Jack Kirby's impending move from Marvel to DC, Fantastic Four #94 debuted in October 1969, a little more than 8 years after the first issue with Jack Kirby as the sole artist. At this point in the run, Jack was getting tired of his treatment at Marvel, with Stan getting more credit for the Fantastic Four than Jack felt he deserved, and Stan constantly underplaying Jack's contributions to the press. More than any other title, The Fantastic Four was the comic Jack's heart was in the most, with speculation and anecdotal evidence citing a large majority of Jack's run being written entirely by himself, with minimal input from Stan compared to other Marvel titles. Many fans feel Jack's work in Fantastic Four #94 to be one of the last great stories Jack would draw before his move to DC, with Jack demanding subsequent issues be plotted by Stan until his departure.

While helping differentiate Marvel enough to beat DC, the Marvel Method of comic creation that Stan Lee employed was a double-edged sword. Prior to Marvel, artists rarely received credit for their work, and Stan Lee helped change that. On the other hand, because of how credits were doled out, artists had a much larger part in writing the stories than was implied, only receiving artist credit while Stan Lee got full writing credit. Unlike most other artists of the time, Jack Kirby also supplied dialogue for stories he wrote written in the margins, which were sometimes ignored entirely, and sometimes included almost verbatim. Perhaps the changes to Fantastic Four #94 were one of the many straws that broke the camel's back for Jack, but either way, we wouldn't have Agatha Harkness or many aspects of WandaVision without Jack Kirby.

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