Cha Joohyeok and Seo Woojin lead an unhappy marriage as busy working parents. One day, Joohyeok is handed something special.

Joohyeok secretly buys a new video game console knowing that he's dead if Woojin finds out. Later, he returns to the mysterious toll booth.

When Woojin begins her new job at the bank, Joohyeok tries to have her transfer to another branch. Lee Hyewon's behavior upsets Joohyeok's parents.

Meeting Woojin's mother startles Joohyeok, who finally learns about her condition. At the bank, Woojin is put in a potentially dangerous situation.

After confessing his feelings to Woojin, Yoon Jonghoo volunteers to join her on an overnight work trip. Horrified, Joohyeok follows them.

A surprise visitor comes to the bank looking for Joohyeok. The three friends agree to go on a getaway together with their partners.

Joohyeok wants to return to the way it was, but it may be too late. When her mother goes missing, Woojin is overcome with worry.

Finding out about Joohyeok's lie infuriates Hyewon. Meanwhile, a malevolent post is written about Woojin on an online community.

After a fight with Joohyeok, Hyewon takes drastic action. Woojin and Jonghoo's co-workers find out about their relationship.

Woojin has something to say to Jonghoo, who later overhears a conversation that stuns him. Hyewon sees the real Jeong Hyeonsoo.

The truth about her unusual connection with Joohyeok becomes clear to Woojin. At work, a sudden emergency places Joohyeok at risk of losing his job.

Finding himself back in 2006, Joohyeok tries all he can to avoid Woojin. When they wake up in the present, life has changed again.

To Joohyeok's distress, Woojin returns to the bank. While she wants to make things work, he remains adamant about pushing her away.

While sneaking around their co-workers on a date, Woojin runs into her charming first love from her university days and makes Joohyeok jealous.

Three years later, Joohyeok and Woojin have come full circle — with revisions. Hyewon shows up at a university club reunion.