Across Doctor Who’s first 21 years the show has simply never been this dramatic. The Doctor has never had an opportunity to be more of a classic hero figure. And no Doctor has had an opportunity to bow out on such a wonderfully perfect story. The best story in many years. The best since Talons which was also written by the master of writing Doctor Who: Robert Holmes. The quality is his only defining feature here with the story, appropriately for this era, being extremely dark.

So many twist and turns and betrayals give The Doctor, awesome new companion Peri and the rest of the cast (including two prominent stand out baddies) an opportunity to truly shine. Every member of the cast pulls their weight though and makes for a flawless production.

Part one kicks off with some incredible matte paintings which are seamlessly blended with the quarry. Even by today’s standards I can’t tell where the seams are. It looks genuinely alien, otherworldly and beautiful.

It’s weird that so many of the fan’s favourite adventures are those that are as deeply dark as this - but it has to be said that there is particular depth to this story. Much has been writing about Graham Harper’s direction but it can’t be underlined enough - he absolutely nailed this. It looks phenomenal. The fact that a quarry could look so alien and that big embarrassing monsters could look so menacing is a triumph.

It’s the end of an era. And a relief in some ways because I’m leaving The Fifth Doctor’s time wanting more after having been fairly lukewarm on it to begin with. Season 21 has been head and shoulders above Davison’s first two seasons. Of course, the season is not quite over yet…!

This was a high water mark for Doctor Who.