After twenty-four years of tender love, Lulu has never been able to fill her heart's confusion about her life experience. Although her adoptive parents' love is warm, they can't solve the obsession of "where do I come from?" An old silver lock engraved with fine lines unexpectedly appears, revealing the past that has been dusted by time, and also puts before her the crucial decision of collecting blood and warehousing it. From being concerned about her adoptive parents' feelings and fearing the fruitless search for relatives, to witnessing the regrets of countless families because of not being connected by blood, Lulu finally mustered up the courage, using a touch of passion as a guide, to transcend the barriers of time, pursue the separation of family members, and bring hope of reunion to her biological relatives.
