Actor Michael Sheard, one of Doctor Who's most prolific guest actors, died today of cancer at his home on the Isle of Wight according to a BBC News report and a statement on the actor'swebsite. He was 65. Sheard appeared six times during the course of the series, with appearances in "The Ark," "The Mind of Evil," "The Invisible Enemy" and "Castrovalva" as well as his most familiar roles as Laurence Scarman in "Pyramids of Mars" and the Headmaster in "Remembrance of the Daleks". Sheard later returned to Doctor Who for Big Finish in the audio "The Stones of Venice" as Count Orsino. He was best known on British television in the role of Mr. Bronson on BBC1's "Grange Hill," and made his mark on popular film as Admiral Ozzel (who met his fate at Darth Vader's hand) in "The Empire Strikes Back", as a U-boat captain in "Raiders of the Lost Ark" and in a brief cameo as Adolf Hitler in "Indiana Jones and the Last Crusade". He was also seen in roles in "Coronation Street," "Dixon of Dock Green," "Crossroads," "Auf Wiedersehen, Pet," "On The Buses," "The Tomorrow People" and countless guest starring roles. Sheard was also a very popular guest at Doctor Who and Star Wars conventions for the past twenty years -- his last appearance was just last month in St. Louis -- and was the author of four books about his memoirs, which included his recollections about years of conventions around the world.