A Transylvanian nobleman called Count Dracula arrives at Baker Street seeking the help of Sherlock Holmes, for his beloved wife Mina has been kidnapped. But Dracula is a client like no other and Sherlock and Watson must confront - despite the wild, unbelievable notion - the existence of vampires. And before long, Sherlock, Watson and their new vampire allies must soon work together to banish a powerful enemy growing in the shadows....