Chinese scientist comes to the US but is kidnapped straight away from the airport and switched for his look-alike, which soon suffers death in mysterious car accident. Young girl who says she's scientists niece comes to Jack 'Extralarge' Costello and asks him to find her uncle. Extralarge starts investigation, but someone doesn't want him to learn the truth and whole case is complicated even more when he finds out that the girl is not the person who she claims she is.