Musician Yoo Tan jumps off the stage and declares his unending love for his girlfriend, Da-in. Seven years later, he seems to have a change of heart.

From the spam phone call to the meeting with an entertainment company representative, everything seems to be a repeat of yesterday for Tan.

After countless days of spending money, partying and gambling, Tan finally starts to wonder how his other band members and Da-in are doing.

Determined to change how the day ends, Tan tries to eliminate everything that can go wrong and decides to take Da-in away on an unplanned trip.

Seven years ago on the day that Tan and Da-in met for the first time, Tan was busking with his band and Da-in became his first audience member.

Da-in makes a deal with the death messenger. On their first anniversary, Tan takes Da-in to an expensive restaurant and prepares a special event.

Tan decides that taking his life first is the only solution to end his agony. The death messenger explains to him how he can stop the time slips.

Again and again, Da-in gets heartbroken and prepares for a breakup. Regardless, Tan continues to compose and practice Da-in's new song.