Securities analyst Chen Che has an accident after arguing with his mother over his father's identity and wakes up in 1989, a year before his birth.

Che begins to adapt to his new situation. After being rejected for a job at the firm where Zhen-zhen works, he makes an impossible bet with a client.

Zhen-zhen insists Che rents a room in her parents' house. Che has to deal with seeing his mother as a happy young woman. Jian gets a new job pitch.

Jian gives Zhen-zhen another chance, but Che's new position in the company causes problems for her. Ya-juan finds Che's behavior a little strange.

Li-jing accuses Zhen-zhen of making a huge mistake. Che thinks about his youth and wonders what changed Ya-juan. A club brawl leads to a revelation.

Che is touched when Zhen-zhen's family learns about her debt. Mr. Wang settles the score in the bowling alley. Che shoots hoops with Jin-qin.

After Che happily bonds with Jin-qin, he begins to suspect that someone else is his dad. Ya-juan's mother disapproves of Jin-qin. Che misses a call.

Xiao-long has a photo shoot that leaves him second best to Che. Ya-juan's mother has an ulterior motive for inviting her friends over for a party.

Che and Zhen-zhen get closer during a thunderstorm. Zhen-zhen and Ya-juan nurse Che through a bad cold that stirs up his childhood memories.

Che saves the day for Ya-juan when a delinquent account holder puts her job at risk. Meanwhile, Zhong-en and Jin-qin are both pining for Ya-juan.

A month after arriving in 1989, Che worries about his identity. Zhen-zhen tries magic to see her future husband. Xiao-long discovers something odd.

Che fills in onstage for Jin-qin at Zhong-en's café. Xiao-long is getting more suspicious of Che. Ya-juan's mother arranges a blind date for her.

Jin-qin tells Ya-juan his future plans. Che accidentally runs into his grandfather, a physicist who has a theory about time, space and wormholes.

Mr. Jian takes the office on a weekend retreat in the country, where some hidden feelings are revealed and others take a path to a new direction.

When an infection sends Zhen-zhen to the hospital, Xiao-long and Che vie for her attention. Che reveals who he is to the only person who can help him.

Xiao-long tries to tell Zhen-zhen about his suspicions. A shady new client gives Xiao-long some advice. Mr. Ye is still confused about Che's suit.

Guo-zhang explains the butterfly effect to Che, who realizes even small changes now can affect the future. Wan-ling and Ya-juan have a huge quarrel.

Xiao-long's drunken call to Zhen-zhen leads to a confrontation. Guo-zhang worries about his own butterfly effect. Che warns Zhen-zhen about Sheng-tai.

Xiao-long becomes the firm's top seller. Zhen-zhen and Che hide their feelings from her parents. A worried Guo-zhang pressures Che about the future.

Che wonders if changing Ya-juan's future will alter his own. Guo-zhang encourages Ya-juan. An angry Wan-ling arrives at the club at the wrong moment.

Ya-juan and her mother grow further apart. Xiao-long plans a lavish Christmas party. Zhen-zhen overhears Che and Guo-zhang talking about time travel.

Zhen-zhen comes up with a dangerous idea to keep her and Che together. Xiao-ling challenges Che to a drinking duel. Zhong-en lashes out at Jin-qin.

Jin-qin misunderstands when he sees Zhong-en comforting Ya-juan. Zhen-zhen's family is happy about Che. Ya-juan makes a decision, and a conclusion.

Xiao-long won't take no for an answer. Che finally tells Zhen-zhen about his connection to Ya-juan, who later reveals what happened on Christmas Eve.

A stock market crisis leads to financial problems for both the Ye and the Chen families. Guo-zhang comforts Ya-juan, who gets life-changing news.