Quite often this year my reviews on this very website have tended towards the negative, and inevitably one starts to wonder if, as a viewer, you are becoming too critical. It's true, three of the eight episodes screened so far have been historicals set in era's of which I'm not especially fond (1930's New York was dreary and clichéd in "Invaders From Mars" and it didn't lose that on translation to TV). Those aside, we've had two above average RTD yarns, always of interest but never all-time greats, a further runaround in "Lazarus" and the dire "42". On the face of it, it's hard to pinpoint exactly what's wrong with that collection of stories (leading to the previously mentioned feelings of "is it me?"). It's been no disaster, no Season 15 run of tedium, but at the same time the season has been short on brain and inspiration. "Lazarus" was one long chase based on an unoriginal premise to start with, and "42" was little more than panic set to words, an attempt to thrill at the expense of anything like subtelty, suspense or characterisation. But with the viewing public seemingly happy, and the mix of wacky future sci-fi, aliens in the past and people in spacesuits being taken over, seemingly unchanged from last year, I was beginning to think that it WAS me. Until now.

"Human Nature" reminds us not just what has been absent from Doctor Who this year until now, but also of the potential that the production team had previously started to let slip through their fingers. It's hard to call Season 3 so far unoriginal as a whole, but perhaps it has been tiredly trying to follow its own three-year old formula too hard ("42", again, even being a wholesale rewrite of "The Satan Pit" and "Gridlock" a third visit to New Earth) without remembering the plethora of possibilities that lay before it back in 2005. Remember that comic strip from the wilderness years, where the artist, Sean, envisaged a number of wonderful evocations of what Doctor Who was, none of which had ever actually appeared on screen? Cybermen bursting through graves, Auton babies and all. It's that kind of rural terror that "Human Nature" tapped into. Now Doctor Who has finally done animated scarecrows (and, for the first time this year, the Sec-Human hybrid aside, we can say "what a truly great idea!") and perhaps they will get round to a seaside adventure at some point too.

This touch of colour made "Human Nature" feel totally unique among it's New Series fellows, and for once none of its locations look like Cardiff. The idea, skilfully lifted from one of the best Doctor Who novels, feels original and exciting... this FEELS like a classic in the making. Above all, for the first time since "The Empty Child" Doctor Who felt not just frightening, but CHILLING. The possessions of Baines and Jenny were the most devious performances since Annette Badland's Slitheen, sure to thoroughly terrify kids for weeks to come. Somewhere in the midst of this, there was an invisible spaceship (one of Shada's best ideas, deftly lobbed in as an afterthought and given the effects treatment it always deserved) and Tennant at the height of his powers. And then to top it all, Paul McGann showed up. Truly, this looks like a story rich on the eye and rich in every other respect too.

Once upon a time, Doctor Who worked out how it could become the series it always threatened to be; one full of Edwardian corridors, war-time schools under threat, Cybermen bursting through graves and rampaging scarecrows. A Doctor Who bristling with history, life, emotion and sheer rural terror. Then, it was via books like "Nightshade" and "Human Nature". Some years later, we seemed to perhaps have hit a creative rut again, and Earthbound adventures meant the streets of Cardiff or always a suburban living room. It was nice, but perhaps some potential was being overlooked. Now, I can say these things because "Human Nature" is back from the past to remind us of how good it really can be. Doctor Who has gone from being good to great and suddenly it doesn't seem so shameful to admit that. Yes, the series so far has been lacking and "Human Nature" is the triumphant proof. I don't think one should be ashamed of not enjoying something, because only through this dissatisfaction can a subsequent re-invention truly be appreciated when it arrives. This week's Who has indeed re-invented the season, and suddenly we have a New Series classic on our hands for the first time in a while.