The Three Investigators presented by Alfred HitchcockA pulp magazine collection in 54 volumes.Until the 1960s, many pulp magazines were published each month in the USA. Some contained mystery tales. Here is a collection of 54 such tales associated with the motion picture director Alfred Hitchcock, the complete series dealing with the trio of detectives known as The Three Investigators.Pulp magazines were a popular form of printed periodical in Britain and America long ago.This is a set of scanned copies of the original pulp magazines, a set of 54 .pdf files, provided by courtesy of:    https://pulpscans.groups.io/g/main