A detective series showing a new angle on the classic story of the great detective from Britain. After the mysterious murder of her mother, young American woman Amelia learns that her missing father may have been Sherlock Holmes himself. So she finds herself on his doorstep with this shocking news. Meanwhile, Sherlock is trying to save Dr. Watson and Mrs. Hudson, who are being held hostage by a criminal syndicate led by Moriarty. A spirited girl comes to Holmes' aid, and he uses his deductive method and network of informants to uncover the secret of her origin. Could he really be her father?