Piers Morgan always dreads heading back to work on America's Got Talent, because he is a regular victim of Howie Mandel's practical jokes. The hit TV show heads back to the small screen this month, and Morgan admits he is not looking forward to spending more time with Mandel, who he has branded the "most annoying man in the history of planet Earth". The British presenter reveals Mandel loves playing pranks backstage, and he has suffered greatly at the hands of his fellow judge. He tells Access Hollywood, "I …More