Mary is a ghost that appeared in The Haunting Hour episode Scary Mary.
When she was alive, Mary was a young woman who was hopelessly obsessed with her beauty, so much so that she could not turn away from her reflection while her farmhouse caught on fire, and she burned to death. Her restless spirit, revolted by her gruesome burned features, waited for someone to chant her name, so she could take their face and once again be beautiful and adored.
To summon Mary, you must hold a candle in front of a mirror in a dark room, and say a poem. Then turn on the lights and look in the mirror at the same time. An insecure girl named Hannah carries out the task, but nothing appears to happen. Days later, Hannah finds a compact hairbrush with an M on it. Later Hannah sneaks out to go shopping for beauty supplies.
When a friend calls her mom says she is grounded. Meanwhile, Hanna is in her room. She is applying make-up and brushing her hair with the M brush she found. Unbeknownst to Hannah, girls with masks are in her mirror. When her mom hears something she finds nothing in Hanna's room. After she leaves, Hannah is revealed to be in Scary Mary's world because the girls in masks broke through the mirror and pulled her in. While in Scary Mary's world, Hannah refuses to be like everyone else, who have given their faces to Mary. Mary uses the girl's faces to disguise herself as one of them, hoping that a boy will come to rescue the girl and take Mary out of her world, but nobody ever comes. Hannah's friend Eric comes to find her and finds Mary with her face and realizes that it's not her. Mary's farmhouse sets on fire, representing what had killed her. He finds the real Hannah in a chest, then gets back to the real world by going in a river full of Mary's tears. At the end Mary calls for Eric, implying that he is going to be taken by her.