Peter Hurkos (Pieter van der Hurk, 1911–1988) was a Dutch psychic who claimed to have discovered his abilities after falling from a ladder in 1941. As a "psychic detective" he took part in high-profile US investigations, including the Boston Strangler and Manson Family murder cases.

Gerard Croiset (1909–1980) was a Dutch clairvoyant and psychometrist, one of the most famous "psychic detectives." After World War II he was sometimes consulted by police on missing-person cases, including the high-profile Australian disappearance of the Beaumont children.