The identity of the dentist who first introduced THE Beatles to LSD has finally been revealed in a new book about the band. THE FAB FOUR: THE GOSPEL ACCORDING TO THE BEATLES by STEVE TURNER claims the man referred to by the late George Harrison as "the wicked dentist", was JOHN RILEY, a distinguished professional with a practice in London's Harley Street. Riley's identity has been shrouded since that fateful occurrence in 1965, but now, 20 years after his death, Turner has decided to life the lid on the sneaky dentist, who spiked the stars' coffees with the drug when they went to dinner with him. John Lennon's first wife CYNTHIA reportedly has still not forgiven him. An insider says, "The book is significant as drugs went on to have a big effect on the band. "When you go for dinner with your dentist, you don't imagine a professional man would do something like that."