Soo-jin (Son Ye-jin) is a rich girl who ran away with her boyfriend but was abandoned. She met Cheol-soo (Jung Woo-sung), who was a worker at a construction company, in a convenience store. In the days to come, they met again and again and finally fell in love with each other. Cheol-soo knew that there was a huge gap between his and Soo-jin's status, so he didn't dare to express his friendship easily. Soo-jin proposed to Cheol-soo. Even if Soo-jin's parents stopped him, the power of their love still convinced their parents. Their married life was sweet, and Soo-jin helped repair Cheol-soo's relationship with his mother. But the good times didn't last long. Soo-jin's memory began to decline day by day. She had Alzheimer's disease and her brain was gradually dying. The disease deeply tortured the two people in love. Soo-jin had a day when she completely forgot everything, but Cheol-soo couldn't leave Soo-jin behind. Can their love help them overcome the test of memory?