We’re halfway through Series 8 of Doctor Who, and I’m beginning to think that this season is as much about Steven Moffat learning from his mistakes as it is about the Doctor learning from his.

This last week’s episode is a perfect case in point. “The Caretaker” explores a theme Moffat covered just last season in “The Power of Three”: what it’s like to try to live an ordinary life when the Doctor’s in it. But that episode never quite succeeded, while this one succeeds quite well.

The difference?

Consequences.

To begin with, “The Caretaker” is really Clara’s story. It starts and ends with her, as she tries to balance her travels with Twelve and her growing relationship with Danny.

Needless to say, she’s not doing very well at that. In fact, she’s not even trying. Oh, she thinks she is, but she’s really just hiding the two most important men in her life – her boyfriend and her “space dad” – from each other. And no good can come of that.

That No Good comes straight to her door, when a temporary caretaker arrives at Coal Hill: a Scot named John Smith. This amuses her significantly less than it amuses us.

(The look on Clara’s face on seeing Twelve in her school is priceless; Jenna Coleman has the best wide-eyed stare this side of Dru Barcus.)

It turns out that Twelve is there to track down and deal with a killer robot whose presence threatens all of humanity (that his past meddlings may have brought said threat to Earth may be lost on him). Just a typical day in his life. For Coal Hill (especially Danny), not so much.

And let’s get this out of the way: The robot is silly. It looks entirely ridiculous. It’s a Macguffin. It exists solely as an excuse to bring Clara’s two lives crashing together.

And what a crash it is. Once Danny and the Doctor finally meet, the episode really comes to life. The dialogue (by Moffat and Gareth Roberts) is rich and sharp. The actors dive into it with relish; the payoff of having Capaldi, Coleman, and Samuel Anderson (as Danny, finally) in the same room is well worth the buildup of the last four episodes.

And best of all, there’s no neat and tidy ending. Nobody gets to go back to their ordinary lives. The Doctor and Danny may understand each other, but they don’t particularly like each other. And Clara is beginning to wonder if Danny’s right, if life with the Doctor is actually more dangerous than she wants to believe.

She’s growing up.

And that’s where the episode ultimately succeeds. Where “The Power of Three” left its heroes right back where they started, “The Caretaker” challenges them. Maybe it changes them. And it builds dramatic threads I want to see woven together.

Looking back on the episode, there’s a sense that THIS is what Moffat was trying to do in Series 7. But maybe it was too early. Maybe it was the kind of story that could only work with this Doctor. Inscrutable. Insufferable. Incomparable.

And whatever road “The Caretaker” has just paved, I’m looking forward to traveling it.

Until the next stop…