Madame Masque is a supervillain, former mad scientist of Hydra and member of the Shadow Council, and the enemy of Iron Man, She is the final antagonist in Season 5: Black Panther's Quest.
For the first time she appears in the animated series, as a scientist of the Hydra organization. She conducted experiments on vampires and Dracula wanted to avenge her on this. The Avengers protected her from the vampire and she became friends with the Hawkie.
She then appears again in the series as a Shield agent. She leads a project to pull out of the ice the ancient royal ship of Wakanda. When they found the ship, it began to sink in the ice and Whitney was forced to wear a mask that allowed her to control the ship. After that, she escaped. She later joined the secret organization Shadow Council. In the last episode of the series, she died while trying to save her ship. She fell into the abyss and allegedly died. She healed the hands of Hawkie and invited him to share with her a new world order. He took advantage of her confidence and shot her ship, after which it fell into the abyss.