I really was looking forward to a triumphant end to the Russell T. Davies years on Doctor Who. And the audacious conclusion of the previous episode, which saw the population of Earth replaced by doubles of The Master, was a creepy and bravura cliffhanger of truly cinematic dimensions to end on. Shame then, that tonight’s final episode, also David Tennant’s adieu from the series, turned out to be such a damp squib.

Really, I should be used to RTD pulling stunts like this. He is without doubt a brilliant showrunner, his imprint on every aspect of the resurrected series — often to breathtaking effect. The choice of Christopher Ecclestone as the first of the new Doctors. The triumphant opening story with Rose, demonstrating that the show could work for the whole family and not just a dog-eared fanbase. And perhaps most importantly, the choice of some truly excellent writers to work on the series — above all others, Paul Cornell and Steven Moffat.

Truth is, many of Russell’s own episodes were the weaker ones of the series. Recall the dreadful business with the London bus stranded on a desert planet offered up as an Easter special. But equally, he can sometimes deliver the goods — the Waters of Mars episode was a triumph, though how much of that was down to his co-writer? Well, I’d like to think Russell was responsible for the excellent stuff that led up to the Doctor’s demise, as the Timelord’s arrogance got the better of him for a while, until the suicide of a woman he’d saved from certain death in the face of his hubris made him realise he was out of control.

So, all that good work building things up, only for the final episode to be such a letdown. An anticlimax at least if you were expecting any sane resolution to the nasty goings-on with the return of the Gallifreyans, and the perfidy of the Master. Instead, the audience were fobbed off with vague handwaving that purported to deal with knotty plotty matters.

A real shame then…but RTD is a master at delivering emotional connections, and the latter chunk of the programme was essentially a greatest hits montage, as the Doctor and his writer revisit characters they have loved and bid them farewell before handing the reins of the show over to Steven Moffat. And, damn you Russell, it worked: my eyes were damp as we got to see Rose again, and I couldn’t help smiling as Captain Jack was slipped a piece of paper with the name of the guy sitting next to him in the nearest I’ve seen to the Star Wars cantina scene in the Dr Who universe.

A pity that Russell emphasises the heart of his story to such an extent that the brain expires from oxygen starvation: this is after all a science fiction show, and some attention to the intelligence that characterises the best of the genre would be welcome. But maybe that’s to come, along with new Doctor Matt Smith, when Mr Moffat takes over. Let’s hope so.

That blend of emotion and intellect can be achieved; Duncan Jones pulled it off in his triumphant debut Moon. And he’s one of the people I’d turn to in Steven Moffat’s situation of being given the keys to the BBC’s best asset. While we’re playing make believe let’s add some others to the list: comics writer Grant Morrison, science fiction novelist Alistair Reynolds, screenwriter Diablo Cody. Which gives you some indication of the problems faced by the people in charge of a series that attracts such attention. Whatever you make of Russell’s tenure on Dr Who, it’s attained a status it never previously had. Here’s to success in his future ventures.