让她跟着海伦，一个自行车快递谁遭受创伤性事故。当她恢复时，她开始体验奇怪的偶发性黑、幻觉和夜的恐惧，导致她发现她有一个肿瘤，一个良性的增长，是一个“消失的双胞胎”在子宫内吸收的残余。随着时间的推移，肿瘤表现为黑暗和疯狂的陌生人的一个版本。随着海伦的情绪和心理状态开始恶化，进一步，她开始采取行动，在精神病发作是由她的邪恶双胞胎的影响-使她自己和她的最好的朋友，莫莉的危险。

  Let Her Out follows Helen, a bike courier who suffers a traumatic accident. As she recovers, she begins to experience strange episodic-black outs, hallucinations, and night terrors-that lead her to discover that she has a tumor, a benign growth that is the remnants of a "vanishing twin" absorbed in utero. Over time, the tumor manifests itself as the dark and demented version of a stranger. As Helen's emotional and psychological state begins to deteriorate further and further, she begins to act out in psychotic episodes that are influenced by her evil twin - making her a danger to herself and her best friend, Molly.