On his return to London after serving in the Second Anglo-Afghan War as an assistant surgeon, Doctor Watson is looking for a place to live. He is introduced to a certain Mr Holmes, an eccentric, pipe-smoking gentleman who shows an interest in chemistry and is currently engaged in a test to detect human haemoglobin. What begins as a simple house-sharing enquiry soon turns into a fully fledged "study in scarlet", a case of blood, murder and betrayal that will transport the reader from the streets of London to the early settlements of Salt Lake City in Utah.