""The Sign of the Four"" is a classic detective novel written by Arthur Conan Doyle, the second novel featuring the famous detective Sherlock Holmes and his trusted companion Dr. John Watson. The story begins with a young woman named Mary Morstan seeking Holmes' help in solving the mystery of her father's disappearance ten years prior. Along with Watson, Holmes takes on the case and discovers a complex web of intrigue involving stolen treasure, revenge, and murder. As they delve deeper into the case, they encounter a variety of colorful characters, including the enigmatic Thaddeus Sholto and his twin brother Bartholomew, the cunning Jonathan Small, and the dangerous Tonga. With Holmes' brilliant deductive skills and Watson's steadfast support, they unravel the mystery and bring the culprits to justice. ""The Sign of the Four"" is a thrilling and suspenseful novel that showcases Doyle's masterful storytelling and the enduring appeal of the Sherlock Holmes series.Sherlock Holmes took his bottle from the corner of the mantel- piece, and his hypodermic syringe from its neat morocco case. With his long, white, nervous fingers he adjusted the delicate needle and rolled back his left shirtcuff. For some little time his eyes rested thoughtfully upon the sinewy forearm and wrist, all dotted and scarred with innumerable puncture-marks.This scarce antiquarian book is a facsimile reprint of the old original and may contain some imperfections such as library marks and notations. Because we believe this work is culturally important, we have made it available as part of our commitment for protecting, preserving, and promoting the world's literature in affordable, high quality, modern editions, that are true to their original work.