Laura Franco is a young actress enduring a cancer diagnosis. She tries to cope after being dumped by her playwright boyfriend Jacob Sullivan, whose play she helped him write prior to their split. Her friend Mazie drives Laura to her childhood home, where she is forced to live following the break-up. During her stay, she hears noises and discovers a monster in the house, living in the closet upstairs. Though initially frightened by him and his demands for her to move out, Laura and Monster bond over their shared love of theater, and Monster agrees to let her stay for two weeks. Monster convinces Laura to show up for auditions to Jacob's play, particularly for the main role which Jacob originally wrote for Laura to star as. Jacob refuses to cast her, instead choosing another actress named Jackie Dennon, but offers Laura to understudy for Jackie instead. Laura struggles to watch Jacob and Jackie's apparent flirtations during rehearsals, but finds solace at home with Monster. Laura invites him to a Halloween party hosted by the theater. He refuses, but arrives later and dances with Laura among the other partygoers, but their fun is cut short when Laura discovers Jacob engaging in sexual activity with a woman, presumably Jackie. Using his powers, Monster distracts Jacob towards a nearby trapdoor that opens and drops him to the floor below, injuring his arm. Laura excoriates Monster for what happened, but he convinces her that Jacob breaking up with her amidst her cancer treatment was not okay. They return to the house to make love. At another rehearsal, Jackie learns from a castmate about Jacob and Laura's past. She later struggles to perform on stage and is berated by Jacob, but Laura comes to her defense, unloading all of her resentment towards Jacob for their break-up. Laura meets Jacob that evening to discuss what happened. They hook up in his office, but Jacob breaks the news that Laura has been removed from the production.