Patrick George Troughton ( March 25 , 1920 â `` March 28 , 1987 ) was a British actor . Patrick George Troughton ( 25 March 1920 â `` 28 March 1987 ) was an English actor most widely known in his role as the second incarnation of the Doctor in the long running British science-fiction television series Doctor Who , which he played from 1966 to 1969 , reappearing in 1973 , 1983 and 1985 .