[2] Born into a family who were Plymouth Brethren, Underwood had his first paranormal experience at the age of nine, when he claimed to have seen an apparition of his father, who had died earlier the same day, standing at the bottom of his bed.
After collapsing at a rifle range at Bury St Edmunds, Underwood was diagnosed with a serious chest ailment which rendered him unfit for active service.
On 15 July 1944, Underwood married at St. Mary's Church in nearby Baldock (his wife, Joyce, died in 2003 after having suffered with Parkinson's disease for 14 years).
For example, his much imitated Gazetteer of British Ghosts (1971)[9][10][11] and Haunted London (1973) - previously unheard of comprehensive and well-researched surveys (or geographical dictionaries or gazetteers) - which, through their encyclopaedic thoroughness, imparted authority to Underwood as an author on the subject of ghost hunting to which he dedicated his life.
According to Hall, the alleged paranormal phenomena from the rectory were the result of natural causes, such as noises produced by rats or flying bats, pranks by local village boys throwing stones at the house, or tramps trying to keep warm by lighting small fires in the rectory.
[14] In his book No Common Task: The Autobiography of a Ghost-Hunter (1983), Underwood came to the conclusion after years of investigation that 98% of the reports of ghosts and hauntings are likely to have naturalistic explanations such as misidentification, hallucination or pranks and he was most interested in the 2% of the phenomena that he believed may be genuine.
In 1976 a bust of Underwood was sculpted by Patricia Finch, winner of the gold medal for Sculpture in Venice (it currently resides with the Savage Club).
[19] In recognition of his more than seventy years of paranormal investigations - Dame Jean Conan Doyle described him as 'The Sherlock Holmes of Psychical Research'[21] - Underwood accepted the invitation to be the Patron of The Ghost Research Foundation (founded in Oxford in 1992), which termed him the King of Ghost Hunters.