11 Times Doctor Who Reinvented Itself

Tom Baker had made his first appearance as the Fourth Doctor one story earlier, but it was in The Ark in Space that Philip Hinchcliffe began serving as the series' producer, and Robert Holmes as script editor. Even though they were initially working with stories that had been commissioned by their predecessors, the two creators made an immediate impression on the series.

Hinchcliffe and Holmes brought a darker, more violent edge to the Doctor's adventures--a distinct gothic horror aesthetic that even reached to the interior of the TARDIS itself. They shifted the emphasis of the series away from modern day earth and UNIT (major parts of the Third Doctor's era), and frequently drew from classic horror movies for their narrative inspiration.

The era was also characterized by a decreasing reliance upon the show's historically popular monsters in favor of new creations. In doing so they crafted one of the most popular and critically regarded periods in the show's history, which only came to an end when both men moved on and the BBC deliberately embraced a lighter tone for the series.