Who would have guessed, twenty years ago when TV Doctor Who was officially deader than a sackful of doornails, that today mainstream writers would be lining up to write for it? Knock Knock is by Mike Bartlett, award-winning playwright (and also author of drama series Doctor Foster, a show that started off pleasingly sudsy and rapidly became batshit insane. Normally we would mean that as a recommendation, but it was too over the top with the psycho even for us).

But Doctor Who's a slippery beast. All your National Theatre and Olivier Awards don't mean nuthin' here, mister. What matters is whether you get the Doctor and the companion right and, more than anything, whether you turn out a script that brings something fresh while at the same time having that indefinable yet instantly recognisable quality of Whoness. And that is far from being as easy as it looks. Did Mike Bartlett get these right? On the first point: sure. On the second point: as we say in these here parts, yeah, nah.

It's only been a few weeks, but we're already used to Bill being the highlight of the episode, and Knock Knock is no exception. We love the way Bill's more sceptical and reflective than her friends, even if it does sometimes come at the Doctor's expense (yeah, we're really not buying that the lifespan thing would have passed the Doctor by) and even if it has its limits (did none of them read the contract?). It seems they've learned their lesson with Clara, who was too often dragged into smartarse territory: Bill's allowed to be clever without the heavy dose of smuggery. Her interactions with her flatmates are nicely done, too: we could see the guy hitting on her thing coming a mile off, but it was beautifully and naturally handled. After the "I'M GAY, ME!" of the season opener, we're relieved that show not tell got the upper hand here: it's a lot more fun when the writer can get who a character is across without shouting it in your face.

Plotwise, however, we find it difficult to believe that having been recently introduced to travel in space and time she's happy to toss it aside for a while to become a student. Would you? Sure, she must be happy to move from chip-slinging to the other side of the counter, but come on. And we could see what they were trying to do as Bill struggles to keep her life with the Doctor separate from her student life, but it all falls a bit flat, especially as her flatmates think the Doctor's a real hep cat. (Obviously they've never seen him play the guitar.) At times it seems like the whole setup's only there to shoehorn in Bill calling the Doctor "Grandfather".

But even hampered by this stuff, Pearl Mackie shines: in fact we think she's lifting her scenes here a lot higher than Peter Capaldi is. Even though a lot of what's happening is pretty by the numbers, she makes all her scenes engaging, whereas the Doctor in investigative mode we found faintly boring at times. This is decidedly a writing not an acting issue: the problem is that there just isn't enough of any interest for the Doctor to do. That also afflicts the supporting cast: too many flatmates, too little time.

And the story? Doctor Who has done this kind of horror before, in the sparkling little gem Hide. Like Knock Knock, it mashes up a classic haunted house story with science fiction and, in the horror aspects, is a genuine chiller. Knock Knock, sadly, just…isn't. When it comes to horror we're the wussiest people in the known universe, so if it didn't scare us, you know it's about as frightening as a packet of jellybeans. It ticks off all the classics: creaking floorboards, banging doors, people being done in one by one et al. However, that's part of its problem: that kind of stuff is beyond familiar, so that even David Suchet (oh, yes. High-class stuff here) doing his best smiley-yet-sinister doesn't bring the chills.

Worse, the plot is simply ridiculous. If the house stuff is all caused by bugs, what causes the Category 4 winds outside? Global warming? What do the banging doors and, come to that, the knocking have to do with the insects? How did David Suchet discover the bugs needed to be fed? Why did they save his mother in the first place, and why did they turn her into wood? How did the music repeating leave Pavel frozen in the door? Do the bugs turn people into wood, turn into wood themselves, eat people, make people turned into wood eat other people or all of the above? And why on earth does the house fall down? Dollop on some handwave garnish if you must, but don't try and build an entire plot out of it.

Despite all of this, it's (mostly thanks to Bill) entertainingish, up to the point when our gallant heroes hotfoot it up the Tower Of Doom. Then the whole thing drops the horror disguise and dives into a bath of saccharine. Yes, it's everybody's favourite the Misunderstood Monster. And to establish this they talk and talk and talk some more. Yawn. Both David Suchet and Mariah Gale fling everything they've got into it, but it's so mawkish they don't stand a chance. Especially when all the flatmates get regurgitated. Everybody lives! Yay.

Bill's brilliance and some fearsome star power aside, it's not interesting enough, or original enough, or logical enough, or scary enough. File under forgettable.



There was a moment here where we were genuinely surprised, and that was when Pavel dropped the needle. We were expecting a club banger, but instead got Bach. Let nobody say they don't know how to shock the audience.


The power sockets are all too old-fashioned to power their stuff, right? So what's powering Pavel's turntable?


Pavel frozen into the door is, in our never particularly humble opinion, a Han Solo in carbonite reference, but we were also rather too forcibly reminded of the paving stone in Love And Monsters. And you never want to be reminded of the paving stone in Love And Monsters.


How convenient that the mysterious bug treatment doesn't keep some (but only some) memories. A massively clunking plot contrivance if ever we've seen one.


They bang on about how this all kicked off seventy years ago, right? And the bugs need brunch every twenty years? In that case, aren't they tucking in their napkins ten years early? (Thanks to Tom Hickey for pointing this out.)


We know it's difficult trying to bring secondary characters alive within a limited time, but having one clap her hands then start bopping like a maniac just because the Doctor starts playing some random music is not the way to do it.


Wouldn't a house where bunches of people disappear on the regular be kinda notorious? It's not like it went unreported.