The police are investigating the murder of the popular actress Liu Meng. Her driver, Weilun, confessed to killing her, but Agent Ag according to the scene and the coroner’s findings, believes Weilun is not the murderer, leaving the case at a deadlock. Alei goes to the hospital, opens his notebook, and a comic related to Liu Meng appears. In the comic, Liu Meng is a highly popular actress who hires a lookalike stand-in named Xiaorou. Xiaorou is better at acting than Liu Meng, which made Liu Meng dislike her and would not tolerate being outshone. Liu Meng intentionally brought Xiaorou to a social event, got her drunk, and handed her over to Boss Luo. Xiaorou screamed for help while Liu Meng was in another room, making no move to save her. Xiaorou was raped by Boss Luo. Heartbroken, Xiaorou asked Liu Meng why she didn’t help, to which Liu Meng replied she was asleep and didn’t hear, advising Xiaorou to find a way to deal with what had happened.
Weilun noticed something was off that night and stayed at Liu Meng’s place. When he knocked to check on things, he heard Xiaorou being assaulted, and Liu Meng sent him away. Weilun waited downstairs until Xiaorou came out; he drove her home, intending to persuade her to report the crime, but Xiaorou was scared because she needed the job to pay off her father’s debts.
Liu Meng often brought Xiaorou to work, dressing them alike so Xiaorou could take over when Liu Meng didn’t want to work. On the road, Liu Meng taunted Xiaorou, and while Weilun was defending Xiaorou, he didn’t watch the road, causing an accident. Xiaorou pulled Weilun from the wreckage, but when she tried to check on Liu Meng, who had glass stuck in her neck, Liu Meng insulted her, telling her to stay by her side. This provoked Xiaorou, who, feeling disrespected and unable to bear it anymore, killed Liu Meng in a fit of rage and threw her body into the river.
When Xiaorou woke up, she was in the hospital, with her assistant believing she was Liu Meng. Her injuries were minor, and though she wanted to clarify she wasn’t Liu Meng, she decided to go along with it due to her father’s incessant demands for money and her guilt over killing Liu Meng. She had the assistant take her to Liu Meng’s home, where she moved in, mimicking Liu Meng’s signature and mannerisms.
The only way to tell Xiaorou apart from Liu Meng was a red mole on Xiaorou’s neck, which she initially tried to hide but later didn’t care about. One day at a filming site, she was greeted by a stranger, but she didn’t know him or his connection to Liu Meng, only smiling back. Later, this man entered her dressing room, threatening her with something in an envelope, telling her to meet him at a specific location if she wanted to know the secret. Terrified, Xiaorou complied, only to be assaulted again. She later learned the man had photos of Liu Meng with some big bosses, but just silhouettes, so not a big deal. However, he had discovered her secret — the mole on her neck. Frightened, Xiaorou started to appease him to keep her secret, but as his demands for money grew, she decided to eliminate him. She drugged his drink during a visit to his home, but he was too cautious; luckily, Weilun arrived in time to save her. Weilun had witnessed Xiaorou killing Liu Meng but kept quiet out of loyalty, and he killed the blackmailer to prove it.
In one scene, Xiaorou played a character who killed her stand-in, mirroring her life. After the shoot, she hallucinated Liu Meng taunting her at home, leading her to stab herself with scissors when she saw her own reflection. Weilun arrived just then. Alei understood that Weilun was an accomplice and now needed to find evidence.
