Adapted for Young Readers: Sir - Our client, Mr Robert Ferguson, has made an enquiry concerning VAMPIRES. Since we are an engineering firm, unfortunately the matter is not one upon which we can advise. Perhaps you can HELP. Holmes and Watson take on their strangest case yet when a distraught husband comes to them desperate to understand his wifes weird behaviour. He's caught her sucking the blood of their baby son! But vampires don't don't exist... or do they?