4P3 - The Deadly Assassin 3

Episode Three of The Deadly Assassin is one of the most famous, most surreal, most artfully crafted, and most controversial episodes in the entire history of Doctor Who. Shot almost entirely on film, it mainly features only two characters - The Doctor and his pursuer, Goth - and continues on from the end of Episode Two by putting our hero through a series of increasingly bizarre challenges within the Matrix.

The results are dazzling. This is Doctor Who like we've never known it before. Tom Baker proves himself to be just as reliable an "action Doctor" as Jon Pertwee ever did, running from airplane gunfire, sliding down hills, falling out of trees, and, in the episode's climax, engaging in a full-on vicious and brutal fight with Goth.

It's the fight, of course, or more specifically, the final few seconds of Goth holding The Doctor's head underwater that raised the heckles of Mary Whitehouse and the National Viewers Association enough to get Philip Hinchcliffe to personally excise the scene from the original master tape to prevent it being seen on any future repeats of the serial. Looking back at the scene, especially in context of where The Deadly Assassin occurs in the series as a whole, it really is just the straw that broke the camel's back. There are scenes containing a great deal more violence and brutality during Seasons 12 and 13, but since the reaction to Goth/Doctor fight actually resulted in the BBC capitulating and admitting it had crossed the line, The Deadly Assassin signaled a change in how Doctor Who would be produced henceforth.

In short, Doctor Who would never be as grim and gritty as this ever again...