A crime thriller about a man who spent a night with a strange woman who doesn't even know his name before getting married.

On the afternoon of the day before her school trip, Se-mi wakes up from her strange dream and heads to her Ha-eun. It was because she felt like she had to convey the feelings she had been holding back for a long time today. However, unlike her overflowing heart, the two keep falling apart.

Unlike Gi-hoon, who is happy running a noodle shop with his mother in their hometown, Ji-eun distances herself from her family due to her ambition to succeed as an idol singer. The siblings, who have been hurting each other more than showing love, find their conflict deepening with the news of their mother's Alzheimer's, whom they thought would stay young forever.