In London's Archangel Lane, there is a bookshop aptly named after its eccentric but whip-smart owner, Book. A former military spy turned maverick detective, Book relishes helping the police solve their most complex murder cases.

He lives happily with his sassy, exuberant wife, Trottie, who owns the wallpaper shop next door. Friends from childhood, they share a deep bond of love and respect for each other, but theirs is a 'lavender marriage' of mutual convenience. For Book is a gay man at a time when homosexuality is illegal. Starring Emmy Award winner Mark Gatiss