Elsa Mars' song on the Halloween night summoned the spirit of Edward Mordrake in episode 3 of "American Horror Story" Season 4. Ryan Murphy, co-creator of the show, has said that Mordrake is an "amazing myth."

In the first part of the Halloween episode, "Edward Mordrake" part 1, Ethel Darling said that if the freaks perform on the Halloween night, they summon the spirit of Mordrake, the man with two faces -- one on the back of his head. He arrives to take a soul of one of the freaks. She also narrated the sad story of Mordrake. He was born in a British noble family. The face on the back of his head used to whisper to him. He tried to kill the face but the face wouldn't die. He soon became mad and was sent to an asylum. Mordrake killed a guard and escaped from there. He joined a freak show and he performed beautiful music. However, the audience were repulsed by his second face. Later, he killed all the freaks and committed suicide.

Speaking about the myth of Mordrake, Murphy said in an interview with Entertainment Weekly, "There are some people who say its real and there are photos online that purport to be autopsy photos and there are other people who say it's not."

There is much debate about whether Mordrake is a myth or was a real person. According to The Human Marvels, the true story of Mordrake has been lost to history. "Anomalies and Curiosities of Medicine," which was published in 1896, features the oldest reference to Mordrake and his deformity. The book says that Mordrake is said to have been an heir of a noble family in England. In the book Mordrake is described as a "young man of fine attainments, a profound scholar, and a musician of rare ability." He committed suicide at the age of 23. He is said to have poisoned himself.

The face on the back of his head, according to "Anomalies and Curiosities of Medicine," was "lovely as a dream, hideous as a devil!" The evil face, which was like a beautiful girl's face, would smile and sneer as Modrake wept. At night, Mordrake used to hear the "hateful whispers" of the second face and it used to set for him "dreadful temptations," the book says. Mordrake called the face "his devil twin."

The second part of the Halloween episode, episode 4 of "American Horror Story-Freak Show," is scheduled to air this Wednesday.