Supernatural. Heart of the dragon.

Twenty two years ago, Samantha said Deanna Winchester lost their mother to a mysterious demonic supernatural force. In the years after, their father, John, taught them about the paranormal evil that lives in the dark corners and the back roads of America... and he taught them how to kill it. When the renegade angel Castiel alerts Samantha and Deanna to a series of particularly brutal killings in San Francisco's Chinatown, they realise the Heart of the Dragon, an ancient evil of unspeakable power, is back! John Winchester faced the terrifying spirit 20 years ago, and the Campbell family fought it 20 years before that - can the girls succeed where their parents and grandparents failed?