4 years old, Danny is fighting illegal underground business activities gangster BartHopkins ornaments) abducted. But Bart told Danny that he was an orphan abandoned in the street. From then on, Danny was completely isolated from the world, was put on a collar, and was kept like a dog in the mysterious room below the office by Bart, and received cruel training. Until the age of 30, the child-minded Danny only knew his master Bart, and was trained to be a killing machine that would rush to kill the opponent without hesitation as long as the master gave an order. He became the undisputed champion in fighting events and made a lot of black money for Bart.
An accidental car accident caused Bart to fall into a severe coma, and Danny also met the blind Sam, Danny's world changed greatly. Sam is an old and kind piano tuner. He is chased by the underworld because he knows many secrets. He lives with his 18-year-old adopted daughter, Victoria, and they hope to make Danny feel the beauty and warmth of humanity that has never been touched before, or even forbidden. Under the influence of friendship, love, patience, kindness, and especially music, Sam and Victoria try to get Danny away from the violent education he had received for a long time, and gradually find himself. But the underworld leader refused to let Danny go easily, and the two would face a bloody fight.
