What is the Mark on Kat's Hand in Wendell and Wild?

Wendell and Wild is the animated film Netflix released for the 2022 Halloween, telling the story of a young child named Kat.

Wendell and Wild was created by Jordan Peele and Henry Selick. It follows the same stop-motion style as Henry Selick's earlier animated project which became a cult classic, The Nightmare Before Christmas.

The film tells the story of Kat, a young girl who was orphaned when her parents died in a car accident. After spending several years in a prison, she gets a second chance when she receives a place in a local boarding school in her hometown.

On the very first day Kat attends school, a classroom accident leaves a mark on her hand.

What is the Mark on Kat's Hand?

Credit: Netflix

The mark on the back of Kat's hand appears to be a full set of teeth on a regular day. It appeared after the octopus Sister Helley brought to class attacked her.
Sister Helley finds out about Kat's mark and tells her that she is a Hell Maiden, a woman who can communicate and agree with demons.

At the beginning, the mark tries to control Kat, but she can fight the control. However, as soon as she makes a deal with the demons to bring her parents back from the dead, Kat's mark glows neon green.

Sister Helley discovers Kat's deal with the demon and reveals that she is a Hell Maiden herself, helping Kat break free from the clutches of the demons.