Because of work, Anna (Lin Jiaxin) went to Shanghai to work. She has always maintained an ambiguous relationship with the cake chef Billy, who likes her very much, but Anna has always been thinking about her ex-boyfriend Ouyang (Lu Yi). Because of a painting, Anna met Siyu (Lin Jiaxin), who looks exactly like her. Siyu bought a painting of her husband Ouyang, but the clerk delivered it to Anna's residence, and the two met. They love the same man. Ouyang was originally a pianist, but suffered from depression. Siyu was originally a painter, but she gave up her hobby for her husband. Anna found out on the Internet that they are each other's doppelgangers. When they were 8 years old, they saw the same self when they were drowning. After the abortion experience ten years ago, they were divided into two identical people again, with the same name, the same birthday, and the same experience, which lasted for ten years until they met. At this time, they decided to exchange identities for three days. Because Anna wanted to live with Ouyang again, Siyu was tired of Ouyang. But they have different ideas. Anna wants to replace Siyu, while Siyu wants to replace Anna's identity and leave Ouyang. Ouyang's illness reminds Anna of the breakup with Ouyang ten years ago, and she also discovers Siyu's conspiracy...