Hayden was a 22-year-old student of Ben Harmon's in Boston. Ben sought comfort in Hayden after Vivien miscarried and became distant. Vivian discovered the affair and in an attempt by Ben to "start over" with his family, he ended things between him and Hayden, and moved his family into the Murder House in Los Angeles. As a result of their liaisons, Hayden became pregnant with Ben's child.
Personality and Appearance
She has shown to be emotionally unstable and vindictive, being very easily angered, and she shouts and cries quite suddenly. However, there are times where she seems to be kind and sympathetic, crying as she plays with Beauregard, and comforting an upset Nora.
In appearance, Hayden has a petite build, auburn hair, and honey-brown eyes. When seen as a ghost, she is bleeding from the mouth in what seemed to be an attempt to gain sympathy from Ben. Currently, she bears the bruises of the shovel that killed her.
Although she didn't appear, Hayden's name was mentioned as the one who had the affair with Ben. 
Hayden calls Ben to tell him she is pregnant. She asks him to come back to Boston to support her while she has an abortion. Ben does so, but leaves suddenly once Hayden enters the operation room, realizing he has 13 missed calls from Vivien. 
Hayden comes to Los Angeles to confront Ben and reveals she did not go through with the abortion. She states that she is keeping the baby and demands that Ben support "their child". She also threatens to tell Vivien. Larry Harvey hits her over the head with a shovel repeatedly, killing her in an attempt to extort Ben. Larry continues digging the hole in the backyard in the spot where Ben would awaken after his blackouts. Ben builds a gazebo over where Hayden is buried. 
Hayden's ghost appears at the door during Halloween after Violet goes missing. She has a devious smirk on her face and seems ready to torture Ben and rat him out to his wife. 
Hayden enters the house and tries to attack Violet in her room. Hayden meets Ben in the basement. She confronts him about her murder. Larry enters and beats Ben unconscious. Larry offers to help Hayden seek revenge by burning the house down. He apologizes for murdering her. She replies that she will deal with him later. She talks to Vivien on the phone, taunting her. She also scrawls "Ask him." on the mirror in Vivien's bathroom. Hayden takes a bath in the bathtub, momentarily feeling as if she is the "lady of the manor". Hayden pretends to kill Hallie in the microwave to terrorize Vivien. In reality, it is an exploding tomato. Hayden attacks Vivien with a glass shard. In order to spare Vivien, Ben admits that he lied and continued cheating with Hayden. Hayden finds out that Vivien is pregnant. She believes that is why Ben urged her to have an abortion. Luke, the security guard, arrests Hayden and brings her to the police. When the sun rises and Halloween is over, Hayden suddenly disappears. 
This episode Hayden's sister confronts Ben with a cop about the disappearance of Hayden, but Hayden is quick to stop this and reassures her sister that she is alive and safe (even though she really isn't). Hayden also gets into a little affair with Travis which ends with her killing him. 
She appears at the very end of the episode questioning what Constance and Moira plan to do after they finish cleaning off the baby. 
Hayden appears with Dallas and Fiona to successfully hang Ben, and also at the end with Tate discussing what he is going to do about his love for Violet. When Constance goes to take Michael away, she is stopped by Hayden, who attempts to keep him, but Travis slits her throat, allowing Constance to escape with Michael. 
- Hayden now shares a grave with Moira. Hayden will now reside as a ghost in the house, as anyone who dies in the house or on the property cannot leave.
- To Ben Harmon: "I'm not a whore, Ben! I matter!"
- To Vivien Harmon: "He said that, in-between my thighs, I tasted like raspberries and cream"
- To Constance and Moira: "Hey, bitches, you get all that slime off my baby yet?"
- To Vivien: "I want what's in your womb."
- To Tate Langdon: "Why does being dead make me so horny?"
- To Tate: "Grow a pair. She's not into you."
- To Travis Wanderly
A baby what, fossil?
- To Ben: "All I ever wanted was for you to love me."
- ↑ While digging for the bones of Moira O'Hara, Madison Montgomery and Behold Chablis come across Hayden's skull, which Madison briefly holds. She dismisses it as Moira's, stating it has "a different vibration", and throws it back into the grave.
- ↑ 2.0 2.1 Episode: Home Invasion
- ↑ Episode: Pilot
- ↑ Episode: Murder House (episode)
- ↑ Episode: Halloween: Part 1
- ↑ Episode: Halloween: Part 2
- ↑ Episode: Rubber Man (episode)
- ↑ Episode: Spooky Little Girl
- ↑ Episode: Birth
- ↑ Episode: Afterbirth