Most Haunted
Many times, former "psychic medium" Derek Acorah was possessed by a spirit, sometimes evil or sometimes "lost and confused".  One such case that exposed Acorah was at Bodmin Gaol, Cornwall.  Before the filming, Acorah had been fed misinformation about a non-existent ghost of Kreed Kafer by the show parapsychologist Dr. Ciaran O' Keeffe. During the investigation, which was later broadcast, he presented the information as fact and even behaved as though being possessed by the fictional ghost. O'Keeffe later revealed Kreed Kafer is an anagram of 'Derek Faker' in a national newspaper. Even though O' Keeffe exposed Acorah, the paper also claimed that O' Keeffe had exposed the rest of the Most Haunted team. O'Keeffe later reported that he had been grossly misquoted and misrepresented in the article, and produced a response outlining his version of the show based on his observations and findings, saying he had exposed Derek Acorah and NOT Most Haunted. The show's presenter and executive producer, Yvette Fielding said in an interview that she believes it was a fake possession.