With her husband based abroad, Meekyung lives alone with her son Soohyun, a senior in high school. One day Soohyun brings home his friend Yongjun, and they become close. Several years later Soohyun is discharged from military service and goes on vacation with Yongjun, but a car accident leaves Soohyun in a coma. Soon after Meekyung discovers a hidden secret about her son and Yongjun.
