After getting into an accident, Sol finds hope through a phone call from singer Seon Jae. Years later, she attends his concert only to witness his death, mysteriously traveling back in time to 2008 when Seon Jae was alive.
Confused Sol realizes she must save Seon Jae, though can't reveal the future. She attempts befriending him, facing difficulties as Tae Sung grows curious about her sudden change and Seon Jae is bothered by her abrupt appearance.
Seon Jae, a talented swimmer, wins gold but gets injured during practice. As he contemplates quitting, Sol tries supporting him, leading to a romantic confession.
In 2023, Sol couldn't prevent Seon Jae's fate but changed the past. Returning to the altered timeline, she's dating Tae Seong while a betrayed Seon Jae avoids her. Sol pursues him relentlessly, eventually getting lost on her journey home.
Sun Jae saves Sol's life, inspiring her to live fully. Tae Seong envies Sun Jae's closeness with Sol. Despite Sol's objections, Sun Jae temporarily joins Tae Seong's band as a vocalist, winning a prize that displeases Sol.
Sol breaks up with Tae Seong thinking he dated her to avoid another girl. Sun Jae attempts to win Sol's heart. Sol tries preventing a future accident. Tae Seong ends up hospitalized after an accident where he encounters someone unexpected.
Sol escapes her captor and Sun Jae rescues her, finding herself back in 2023. Her legs are healed, she works in film production. Hyun Ju and Geum are married with another child on the way. Sol attends Sun Jae's concert to reunite with him.
Sol and Sun Jae reunite as promised at Hangang Bridge. Fearing separation, Sol convinces Sun Jae to spend the night together, leading to a realization of their feelings. An unexpected incident leaves Sol distressed.
A new attack leaves Sun Jae critically hurt. The changed timeline prompts Sol's time travel to his college as a student. Paths repeatedly cross despite her efforts to avoid him. Sun Jae gets a US rehab training opportunity.
Sun Jae informs Sol about his rehabilitation training in the US. In Hyuk invites Sun Jae to audition with his band. Tae Seong learns of Sol's kidnapping and visits her. Sun Jae departs for the US.
After admitting their feelings, Sol and Sun Jae cherish their time together. A misunderstanding leads to Kim's arrest. In Hyuk's band performs for the last time while trying to help him.
Kim escapes with Sun Jae, who protects Sol. They meet Geum and Hyun Ju, learning of their bond. In Hyuk quits the band, returning home. Sun Jae, Sol, and Tae Seong visit him, saying Eclipse may debut. Sol notices the future has changed.
Sol leaves Sun Jae after lying to him. He returns to Seoul. Attempting to find her Sol ignores his calls. Meanwhile, she conspires with Detective Kim to trap Kim Young Soo, exploiting her foreknowledge of an incident's timing and location.
After a mix-up at an award show, actor Sun Jae becomes obsessed with a script Sol wrote, determined to star in it despite her protests. As the situation spirals, Sol contemplates quitting her job.
Sol passes out on a Ferris wheel. Sun Jae takes her home, developing feelings for her despite her desire for boundaries. Sun Jae experiences visions around Sol. He joins her movie, but she quits before a meeting.
After regaining his memory, Sun Jae reconciles with Sol, thanks to Tae Seong's help. Eager to propose, he decides to attend Sol's nephew's first birthday party to meet her family.