A montage of how our "monsters" became who they are:

Opening on Sally, dead with blood under her head. Trying to speak to people at her funeral. She stands in front of Danny, her fiance, as he leaves the house they shared together.

Aidan in his revolutionary war uniform. Running into Bishop. Awaking on a pile of dead bodies, his eyes black.

Josh is at a campsite, his friend dead beside him as the police rummage through the wreckage of the site.

Bishop is talking to a girl, Rebecca, on a bed, as she screams for Aidan.

Locked in the basement room of the hospital, Emily tells Josh he is scaring her, as he screams for her to stay way. In a moment of clarity, Aidan gets his phone message plea for help, and arrives just in time to remove her from the room as they watch Josh transform.

Aidan and Emily are in the hospital commissary, talking. Aidan tells her he has a condition, but she should ask him for the details. He tells her that Josh speaks of her often, that while he was studying how to save lives, she was actually living hers. Josh's mom also went crazy (which is what Emily believes happened to Josh).

Josh arrives home, and Sally apologizes that she was unable to help. She tells him Aidan Danny is coming over. She is beyond excited. When he arrives, she is unable to help herself and causes lights to flash and break.

Danny asks if anything weird has happened since they moved in. Suggesting it's creepy. He goes on to tell them about the night Sally died. That the faulty electrical caused her to take a wrong turn on the way to the bathroom and fall down the stairs to her death.

At the hospital, the new girl, Cara, propositions Aidan to explore what they have. As Aidan looks at her, his heart beats heavily in his ears.

Josh walks outside the hospital and sees someone looking at the memorial for the lost nurse. Rebecca. Rebecca grabs him and tries to bite his neck. She is a vampire. Josh confronts Aidan about him turning Rebecca into a vampire.

Aidan goes to Sapp & Sons Funeral Home, which is run by Bishop. Aidan says he asked for a favor, a clean-up, and that they had no right to turn her.
Sally is sitting at a table, trying to blow paper. A knock at the door – it's Danny.

Sitting outside, Josh sees Emily by the hot-dog cart, and they talk. She says she saw it yesterday, and asked if it gets worse. He tells her his life is dangerous, and gets much, much worse. She won't allow him to walk out of her life again.

Sally hovers in Danny's personal space as he tries to read the Plumbing for Dummies book to fix the sink. She talks to him. She gets upset and causes the pipes to burst. She wants him to stop ignoring her.

Aidan sees Rebecca in the park. She is angry that he left her for dead. He admits he got weak with her. He had no idea they would turn her. She looks back at her life and feels so much stronger as a vampire. She wants to hurt people, make them pay for her worthless life. Aidan walks away.

Josh and Sally talk about who they were before they were monsters. Sally wants to try to get Danny to see her, even if it means she loses him all over again.
Aidan is at the bar, and Cara comes over to say hello. He asks her to sit. The sound of blood pumping fills his head. He calls Josh, asks him to come to the bar. Josh says “don't” and says he will be right there.

Rebecca shows up and their resemblance is obvious. Cara realizes that this is the Rebecca who is missing from the hospital. Rebecca wants to eat and have fun. She tries to take a man outside, and Aidan stops him. In doing so, Rebecca takes Cara instead. Josh finds Cara bleeding in the alley, Aidan refuses to turn her to save her, and they take her to the hospital.

Sally tries to reenact her death on the stairs.

Josh sees his sister and Jackie leaving the hospital. He tells her his life is different, she can't help him and she doesn't want to know him. To leave him alone.

Cara dies. Bishop is disappointed and asks Aidan if it will be “us or them.” Aidan said it was never much of a question, he chooses them.

Josh and Sally talk about Aidan, and Josh realizes he never understood just how hard it is every second of every day for Aidan to be who he is. He goes outside to comfort his friend.