Mr. and Mrs. Howard (Brock Doom and Vera King) are supposed to be on their way to visit family for the weekend but, at the very last moment, their daughter, Susan (Alina Lopez), has fallen ill and won't get out of bed. Susan lays under the covers with a thermometer in her mouth, looking clammy and disoriented. 'She's 18-years-old for goodness sake,' Mr. Howard barks, frustrated at the prospect of being late. He urges his wife to let the girl stay home alone. Mrs. Howard seems less convinced. What if she's faking it? What if they could find a last minute babysitter? What if they just cancelled the trip altogether? After some bickering back and forth, the parents finally decide that it's best for Susan to stay home while they go on the trip. Susan promises them that she'll get some rest and take care of herself and her parents leave. Susan lays quietly, listening to them exit, before slowly sitting up and pulling out the hot water bottle she used to fake her illness. A grin crosses her face. Finally, the house to herself -- all weekend!With her parents away, Susan is enjoying her sweet freedom and dancing in her underwear when she is suddenly interrupted by her phone ringing. She picks it up but all she hears is a strange sound on the other end, as if someone is breathing heavily. When no one responds to her repeated greetings, she hangs up, puzzled.A moment later, the phone rings again and when Susan picks it up she hears the same, strange sound. 'Is this some kind of crank call? Lisa.... Is that you??' She laughs into the phone before hanging it up. Instantly, the phone rings again. She picks it up. She hears the same sound of heavy breathing on the other end of the line. She's starting to get freaked out now. 'Mom? Dad? Is that you?' She says cautiously. 'Who is this?' The breathing quickens before cutting out abruptly. Susan puts the phone down and shakes her head. She won't let her nerves get the best of her! Later that night, Susan watches a movie on the TV in her room. She has forgotten about the crank call and is now engrossed in the scary movie. From outside, somebody sneaks up to the window and begins to watch her. Suddenly, Susan is startled by a loud banging. She freezes before looking outside the window. She sees nothing. She hears another loud bang coming from her door. In a panic, she creeps towards the knob. Someone is inside the house! Summoning up all her courage, she opens it. No one is there. The hallway is dark and quiet. Susan breathes a sigh of relief. But then, the doorbell begins to ring wildly. Her eyes go wide in fear. Susan rushes to the front door. She nervously cracks the door to discover a teenage girl (Gia Paige) standing outside. 'Help me! Help me!' She screams. Terrified, Susan opens the door wider and the stranger bursts in, slamming it behind her. 'We have to hide,' she continues. 'Before it finds us!' She pulls the stunned Susan back into her bedroom, slams the door and turns off the lights. Slowly, the room becomes illuminated again by a colorful light. The stranger has pulled a magic screen from her backpack ... with all the pegs glowing. 'It doesn't like bright lights,' she whispers before starting to take off her dirty clothing. Susan can barely keep up. Who are you? What is going on? Should we be calling the police? The stranger catches her breath. 'My name is Amy. I'm 19 years old. I've just escaped from its clutches!' Susan stares at her in shock. 'It's been holding me hostage for months, trying to get inside me. It's a government cover-up. In a warehouse. Lots of medical equipment. Some kind of mutant. It doesn't like bright lights. Listen, I need you to touch me! I need you to take off all of your clothes and touch me! It's the only way to stop it from getting inside!' Susan stands up and turns on her bedside light. Before Susan knows it, she and Amy are wrapped in each other's bodies. Will this be enough to keep the mysterious creature at bay? And what is Amy NOT telling Susan?