Drama also known as Lost And Found: The Billionaire's Son Returns; The protagonist, once the son of a wealthy tycoon, is kidnapped by the tycoon's adopted son and separated from his family. He later joins the Hidden Wolf Special Forces, growing up to become their captain, known as the Wolf King. Just as he is about to reunite with his father, the adopted son poisons him in a betrayal. In a desperate escape, he is injured and loses his memory, only to be saved by his sister. For eighteen years, the tycoon searches for his son, scouring the nation until he finally finds him in Yang City. Just as the butler brings the protagonist to meet his father, unforeseen events occur. The adopted son intervenes once more, threatening the protagonist by putting his sister's life at stake.