It is nearly Halloween and Paige has just broken up with her boyfriend Tommy after she caught him cheating... again. A Halloween gift package with a note, flowers, and a teddy bear were left at Paige's front door and she reads from the love letter with tears in her eyes. Her friends Mary and Cassie are trying to console her, but really they are just working to convince Paige to go out and party with them that night; both Mary and Cassie are dressed up in costume and ready to go while Paige is busy crying in her sweats. Mary wears a skeleton outfit while Cassie embodies a cheerleader with pigtails. The friends listen patiently and exchange eye rolls as Paige reads the note. They tell her she did the right thing by breaking it off with Tommy, saying that a teddy bear and love letter can't make up for his cheating behavior. But they are unaware that there is more to the teddy than meets the eye -- it contains a hidden camera streaming the conversation between the girls. A masked man watches the live feed from his hiding place in the basement…
After much convincing from her friends, Paige decides not to text Tommy back and that she will join the group for a night of drinking and partying. Mary and Cassie are satisfied with their victory and Paige goes to another room to get changed into her red riding hood costume while her friends start drinking. With the masked man still watching from the teddy cam, Mary and Cassie gossip behind their friends back with Mary claiming she would let Tommy cheat on her all he wants because his family money would be worth it in the long run. Mary is grossed out by Cassie’s behavior and goes down to get them more drinks. Paige gets dressed up in costume and does her makeup while listening to music loudly.
Mary goes to the fridge in the kitchen to grab some more drinks for her and Cassie. But she is unaware of the masked invader sneaking up behind her… A gloved hand covers her mouth tightly while his other wraps around her neck in a tight chokehold. She struggles to fight him off but she is too weak and he has caught her by surprise from behind, ensuring there is little she can do to get away. Mary tries to scream out but it is muffled in the attacker's hand. He holds on tight following her every movement. Mary’s eyes roll and her tongue protrudes as she gasps for air. The invader holds on tight and then guides Mary to the ground as she grows weaker. He savagely bashes her head against the floor, knocking Mary out cold.
The masked invader stands up over his unconscious victim and walks over towards her feet. He picks up one of her legs and delicately removes the skeleton stocking from one of her legs. He walks back towards her as Mary begins to wake up and make sense of the situation. Before she can make a move the stocking is wrapped tight around her throat and cuts off her air supply. Her feet kick in the air as the attacker moves both hands around her throat and throttles her on the floor. Mary spasms and struggles but it is no use. The killer squeezes relentlessly and holds his helpless victim in place under him. Mary fades away as she is strangled to death, her spittle caught up in her throat and frothing out of her mouth. Mary spasms and shakes and dies there on the floor, her eyes losing focus and gazing off in a death stare. The killer examines her closely then creeps out of the kitchen, dragging the body along with him.
Paige is still getting ready, putting on each piece of her costume. The sound of the loud music drowns out all other noises while she remains blissfully unaware what is going on in her house.
Cassie lounges on the bed taking selfies in her dress and waiting for Mary to bring her another drink. She is interrupted by a knock on the door and assumes it is her friend playing a prank. Cassie doesn't want to go get the door but as the knocking continues she has no choice. When she opens the door, Cassie is surprised to see the masked man looming over her and staring down at her. Cassie is taken aback, assuming Tommy is playing some joke on them. He enters the room as Cassie backs up while he approaches her silently. Cassie tells him he better leave them all alone, but he has her cornered against the bed, shushing her to stop her talking. Cassie is scared silent so he uses the opportunity to slide both his hands around her neck and squeeze tightly. Cassie was not expecting this crushing force and she fights desperately against it. Coughing and gagging, trying to get away, but the killer has her in his clutches. They struggle back and forth as she pushes against the attacker holding on to her neck tightly. With a hard punch to the side of the face, the attacker sends Cassie tumbling down onto the bed.
Cassie pleads for mercy, asking not be hurt any further. But the masked man methodically grabs her pigtails and wraps them tightly around Cassie’s throat. She kicks her feet out in the air and gripping at the hands around her neck trying to break free. The killer squeezes tightly and Cassie’s face gets more and more red as the pressure builds unrelentingly. She is strangled out on her back on the bed, spasming and swatting away until she gets weaker and her eyes lose focus, eventually locking off in a death stare. The killer moves her body around on the bed and examines her closely. Then the sound of the music from Paige's room draws his attention and he creeps out into the hall towards his final victim. The masked man waits outside of Paige's room where she is getting changed and thinks up his next move.
Paige finishes her makeup and hair, satisfied with her Little Red look and ready to go out with her friends. She grabs her phone and goes into the hall, heading towards the other bedroom. When Paige enters the room and looks up from her phone, she is met with the shocking site of her deceased friends splayed out with their death expressions frozen on their faces. Before she can process the situation or react, the masked man emerges from his hiding place behind the door and lunges out with a chloroformed rag, wrapping it around Paige's mouth and nose and forcing her to breath in the noxious fumes. She struggles and tries to scream but it is muffled by the rag held tightly to her mouth. Paige's eyes roll as she struggles, trying to hit the attacker behind her but it is no use. The panic hyperventilation has caused the drugs to work quickly and soon the masked invader is guiding Paige's unconscious body down to the floor.
Paige wakes up some time later, tied up to a chair in her room with her legs bound to the chair, her hands tied behind her back and her mouth gagged with duct tape. Paige wakes up slowly, the terror of the situation dawning upon her. She tries to move but is unable to break the binds. She tried to cry out but her mouth is muffled by the duct tape wrapped tight around it. The masked man approaches his frightened victim and taunts her, showing off the teddy bear camera he has been using to observe them. Paige is terrified and crying out in panic but gets silent as the masked man holds up a knife to her lips and shushes her. He removes the duct tape from her mouth so they can properly converse. After initial confusion, Paige realizes that this masked killer is not her ex-boyfriend Tommy. The masked man smirks down at her and then slowly removes his mask to reveal his face. Paige recognizes him -- it is Derrick, a stalker who Paige has had to reject in the past. Done with the six years he has spent pining over Paige, Derrick's psyche has cracked and his lovelorn heart has driven him to become a serial murderer. He expresses his love for Paige and frustration that she always ignored him. Paige reminds him that he would stalk and harass her which sets Derrick off in anger and he slaps her hard across the face. He tried to calm himself down, doesn't want to scare Paige away now that he has this chance with her. He expresses his newfound joy of killing, how he can never go back to the real world after this grisly incident. He proposes a new plan to Paige, one where they can run off together and take care of the world's problems as they see fit.
Paige smiles at her captor, hoping that the best course is to play along as long as she can. She pretends to agree with all of the insane things he has been talking about and Derrick is ecstatic that his plan worked. He hurriedly unties her feet and then the hands behind her back. Telling her all they have to do is bury the bodies and then they will be free to escape. Paige nods and smiles along as Derrick begins to detail his twisted idea, then jabs him in the chin with an uppercut that sends Derrick sprawling to the floor. Paige makes a break for it, but Derrick is too fast. He grabs on to her ankle which brings Paige tumbling to the ground. He grabs on to her as she tries desperately to crawl away. Grabbing on to her legs and moving in close, then sitting on top of her and keeping her in place while wrapping both hands around her throat in anger. Derrick squeezes tight as Paige whimpers in pain, kicking her feet out and sliding them uselessly across the floor. Derrick's rage-filled face transitions into a sick smile as he leers down at Paige while choking her to death. He is too powerful and Paige has no chance at escape as she writhes in agony on the ground. Derrick recites the love letter which he had sent to her while choking her out. After a struggle Paige arms flow down on the floor, her feet twitch and stop kicking, and then her face relaxes into a death stare. Derrick lets go of her neck and falls back as he catches his breath, exhausted. He looks down at his newest victim with a smile. Derrick closes his eyes and imagines what could have been… Waltzing with a smiling Paige as her ecstatic friends toss rose petals around the happy couple.