For many years I was the personal attorney and constant companion of Mr. Philo Vance; and this period covered the four years during which Mr. John F.-X. Markham, Vance's closest friend, was District Attorney of New York. As a result it was my privilege to be a spectator of what I believe was the most amazing series of criminal cases that ever passed before the eyes of a young lawyer. Indeed, the grim dramas I witnessed during that period constitute one of the most astonishing secret documents in American police history.
Of these dramas Vance was the central character. By an analytical and interpretative process which, as far as I know, has never before been applied to criminal activities, he succeeded in solving many of the important crimes on which both the police and the District Attorney's office had hopelessly fallen down.
Due to my peculiar relations with Vance it happened that not only did I participate in all the cases with which he was connected, but I was also present at most of the informal discussions concerning them which took place between him and the District Attorney; and, being of methodical temperament, I kept a complete record of them. It is fortunate that I performed this gratuitous labor of accumulation and transcription, for now that circumstances have rendered possible my making the cases public, I am able
