By 1966, Doctor Who was a well known program and drew millions of viewers on a regular basis. Its success seemed to be confirmed but behind the scenes, trouble loomed overheard. In 1965, the show went through a turbulent year with many rapid changes to the production team and a feeling of discontent permeated the team. Many in the team found it troublesome to work with the aging Hartnell and Hartnell himself found the heavy workload increasingly difficult to cope with. And so, in 1966, following the introduction of Shaun Sutton as the new Head of Serials at BBC, the cry for change was finally heard and it was decided that William Hartnell had to be let go. Unbeknown to everyone at the time, a change that stemmed from necessity would end up becoming the series’ biggest boon.