Dr James Mortimer, M.R.C.S. is a British physician and client of Sherlock Holmes. After working for two years in a junior capacity at Charing Cross Hospital, he married and moved to Dartmoor to set up a country practice, where he made the acquaintance of the Baskerville family of Baskerville Hall. After the mysterious death of Sir Charles Baskerville, Dr Mortimer sought out Sherlock Holmes' help in protecting the only remaining heir, Henry Baskerville.