Sussex ( /ˈsʌsɨks/; abbreviated Sx), from the Old English Sūþsēaxe ('South Saxons'), is an historic county in South East England corresponding roughly in area to the ancient Kingdom of Sussex. It is bounded on the north by Surrey, east by Kent, south by the English Channel, and west by Hampshire, and is divided for local government into West Sussex and East Sussex and the city of Brighton and Hove. The city of Brighton & Hove was created a unitary authority in 1997, and was granted City status in 2000. Until then Chichester had been Sussex's only city.

Sussex has three main geographic sub-regions, each orientated approximately east to west. In the south-west of the county lies the fertile and densely-populated coastal plain. North of this lie the rolling chalk hills of the South Downs, beyond which lies the well-wooded Sussex Weald.

The name 'Sussex' derives from the Kingdom of Sussex, founded by Ælle of Sussex in 477 AD, which in 825 was absorbed into the kingdom of Wessex and the later kingdom of England. The region's roots go back further to the location of some of Europe's earliest hominid finds at Boxgrove. Sussex has been a key location for England's major invasions, including the Roman invasion of Britain and the Battle of Hastings.

Sherlock Holmes ( /ˈʃɜrlɒk ˈhoʊmz/) is a fictional detective created by Scottish author and physician Sir Arthur Conan Doyle. The fantastic London-based "consulting detective", Holmes is famous for his astute logical reasoning, his ability to adopt almost any disguise, and his use of forensic science skills to solve difficult cases.

Holmes, who first appeared in publication in 1887, was featured in four novels and 56 short stories. The first novel, A Study in Scarlet, appeared in Beeton's Christmas Annual in 1887 and the second, The Sign of the Four, in Lippincott's Monthly Magazine in 1890. The character grew tremendously in popularity with the first series of short stories in Strand Magazine, beginning with A Scandal in Bohemia in 1891; further series of short stories and two novels published in serial form appeared between then and 1927. The stories cover a period from around 1880 up to 1914.

All but four stories are narrated by Holmes's friend and biographer, Dr. John H. Watson; two are narrated by Holmes himself ("The Blanched Soldier" and "The Lion's Mane") and two others are written in the third person ("The Mazarin Stone" and "His Last Bow"). In two stories ("The Musgrave Ritual" and "The Gloria Scott"), Holmes tells Watson the main story from his memories, while Watson becomes the narrator of the frame story. The first and fourth novels, A Study in Scarlet and The Valley of Fear, each include a long interval of omniscient narration recounting events unknown to either Holmes or Watson.