An addictive and exciting puzzle book based on 500 years of British espionage history, drawn direct from the catalogues of The National Archives After Murdle comes Spydle... Following last year's bestselling phenomenon, the National Archives and Britain's leading puzzle master, Dr Gareth Moore, have teamed up to produce a brand new puzzle book, Spydle, which promises to perplex and excite with tales of espionage and intrigue drawn straight from official records of over five centuries of British spycraft and crpytography.