“In the year 1878 I took my degree of Doctor of Medicine of the University of London, and proceeded to Netley to go through the course prescribed for surgeons in the Army...”
A Study in Scarlet is a detective mystery novel written by Sir Arthur Conan Doyle, introducing his new characters, "consulting detective" Sherlock Holmes and his friend and chronicler, Dr. John Watson, who later became two of the most famous characters in literature.
Conan Doyle wrote the story in 1886, and it was published the following year. The book's title derives from a speech given by Holmes to Doctor Watson on the nature of his work, in which he describes the story's murder investigation as his "study in scarlet": "There's the scarlet thread of murder running through the colourless skein of life, and our duty is to unravel it, and isolate it, and expose every inch of it." (A "study" is a preliminary drawing, sketch or painting done in preparation for a finished piece.)
The story, and its main characters, attracted little public interest when it first appeared.

“I should do so,” Sherlock Holmes remarked impatiently.
I believe that I am one of the most long-suffering of mortals; but I’ll admit that I was annoyed at the sardonic interruption...”
The Valley of Fear is the fourth and final Sherlock Holmes novel by Sir Arthur Conan Doyle. It is loosely based on the Molly Maguires and Pinkerton agent James McParland. The story was first published in the Strand Magazine between September 1914 and May 1915.
At the outset of the novel, Sherlock Holmes receives a mysterious cipher message from a man who writes under the pseudonym Fred Porlock, an agent to Professor Moriarty. Porlock occasionally sends Holmes insider information. Moriarty is blameless in the eyes of the law, but Holmes knows him to be "the controlling brain of the underworld." Together Holmes and Watson decipher Porlock's message which relates that a man named John Douglas, residing at Birlstone, is in danger.

“I am afraid, Watson that I shall have to go,” said Holmes as we sat down together to our breakfast one morning.
“Go! Where to?”
“To Dartmoor; to King’s Pyland...”
The Memoirs of Sherlock Holmes is a collection of Sherlock Holmes stories, originally published in 1894, by Arthur Conan Doyle.
The eleven stories of the Memoirs are:
"Silver Blaze" Clients: none; "The Adventure of the Yellow Face" Client: Grant Munro; "The Adventure of the Stockbroker's Clerk" Client: Hall Pycroft; "The Adventure of the Gloria Scott" Client: Victor Trevor; "The Adventure of the Musgrave Ritual" Client: Reginald Musgrave; "The Adventure of the Reigate Squire" Clients: none; "The Adventure of the Crooked Man" Client: Major Murphy; "The Adventure of the Resident Patient" Client: Arguably Dr Percy Trevelyan (Trevelyan was sent to Sherlock Holmes by Mr. Blessington); "The Adventure of the Greek Interpreter" Client: Mr. Melas; "The Adventure of the Naval Treaty" Client: Percy Phelps; "The Final Problem" Clients: none.

“To Sherlock Holmes she is always the woman. I have seldom heard him mention her under any other name. In his eyes she eclipses and predominates the whole of her sex...”
The Adventures of Sherlock Holmes is a collection of twelve short stories by Arthur Conan Doyle, featuring his fictional detective Sherlock Holmes. It was first published on 1892. The stories are not in chronological order, and the only characters common to all twelve are Holmes and Dr. Watson. As with all but four of the Sherlock Holmes stories, those contained within The Adventures of Sherlock Holmes are told by a first-person narrative from the point of view of Dr. Watson.
In general the stories identify, and try to correct, social injustices. Holmes is portrayed as offering a new, fairer sense of justice. The stories were well received, and boosted the subscriptions figures of The Strand Magazine, prompting Doyle to be able to demand more money for his next set of stories. stories, picking "The Adventure of the Speckled Band" as his overall favourite.

«Creo que es difícil encontrar una vida más variada que la mía en cuanto a experiencias y aventuras. He conocido la pobreza y cierta prosperidad económica. He departido con muchos de los hombres más notables de mi tiempo. He disfrutado de una larga carrera literaria, tras una formación médica coronada con el doctorado en Edimburgo. He practicado muchos deportes, entre ellos el boxeo, el críquet, el billar, el automovilismo, el fútbol, la aeronáutica y el esquí, y he sido el primero en introducir este último en Suiza para desplazamientos largos. He ejercido de médico en un ballenero durante siete meses en el océano Ártico, y después en un barco comercial por la costa de África Occidental. He participado en tres guerras: la de Sudán, la de Suráfrica y la guerra con Alemania. Mi vida ha estado pespunteada de aventuras de toda suerte. Finalmente, me he visto obligado a dedicar mis últimos años a contar al mundo el resultado de treinta y seis años de estudio del ocultismo, a fin de hacerle ver la trascendental importancia de esta cuestión. Con esta misión he recorrido más de cincuenta mil millas y pronunciado conferencias ante más de trescientas mil personas, además de escribir siete libros sobre el tema. Tal es la vida que cuento detalladamente en mis Memorias y aventuras.» Sir Arthur Conan Doyle

Pocas veces en la historia de la literatura un personaje de ficción alcanza tal celebridad que incluso oscurece la figura de su propio creador, y el caso de Sherlock Holmes es uno de los más representativos. Primera novela del mítico detective, “Estudio en escarlata” gira en torno a un crimen cometido en Londres y cuya trama se relaciona con la secta mormona y su cuna, el estado de Utah. “El valle del terror” suma a las habituales dosis de intriga y aventura ingredientes tan atractivos como la inquietante sombra del principal adversario del detective, el archicriminal Dr. Moriarty, que planea a lo largo de toda la novela.

Pocas veces en la historia de la literatura un personaje de ficción alcanza tal celebridad que incluso oscurece la figura de su propio creador, y el caso de Sherlock Holmes es uno de los más representativos. Segunda novela de las cuatro protagonizadas por el brillante detective, “El signo de los cuatro” gira en torno a los avatares de un fabuloso tesoro en la India colonial, y en sus páginas se consolidan los sugerentes y pintorescos rasgos de la singular personalidad del investigador. En “El sabueso de los Baskerville”, Holmes, trasladado a los inhóspitos y desolados páramos de la región de Dartmoor, se enfrenta al reto de resolver un enigmático crimen relacionado con el espectro de un perro diabólico y sobrenatural, instrumento de la maldición que pesa sobre una familia.