Once again it’s easy to see the antecedents for this episode. There are a few intentional shout-outs to the Third Doctor’s era — the “Hai!” karate-chop (“Venusian aikido,” he used to call it), the Miniscope theory. You might also think fleetingly of classic season 11’s “The Time Warrior,” in which a spaceship crash-lands in medieval England and enlists slave labor to help it get off the ground again.

But the most obvious is season 16’s “The Androids of Tara,” which features not only an almost identical title but also a pseudo-medieval setting, a dashing young nobleman, a bearded villain (Count Grendel) who uses human-seeming robots to do his dirty work, not one but two lovely brunettes who look a lot alike, and of course a climactic swordfight and a death-defying plunge into a moat.

Not that any of this trainspotting makes much difference to whether “Robots of Sherwood” is any good in itself. The central problem is that it’s clearly meant to be one of this season’s comedy episodes — a wise move given how grave the previous two stories frequently seemed — but has only a handful of jokes that are actually funny. Many of the rest seem written for Matt Smith (and perhaps they were), and almost all of them are maybe one more script editing punch-up from being serviceable. Humor is a subjective thing, but “I see what you did there” is not the same as a laugh.

And it isn’t just the jokes that seem more Smith than Capaldi. The tension driving the relationship between Clara, the Doctor, and Robin Hood is based on a jealous oneupsmanship contest between the latter two for the admiration of the former, which seems out of keeping with the Doctor’s mature disavowal of this attitude in “Deep Breath.”

We can read it differently — Dad competing with the new boyfriend for his daughter’s admiration — but this doesn’t necessarily make it less awkward. I can’t decide if this dynamic would have been better with Smith, or just more natural, but this is the first episode of the season where I acutely felt his absence.

That said, Capaldi’s once again fine, fun to watch in his own right, and the cast of this fairly silly story is generally quite good, particularly Ben Miller, tasked with following Alan Rickman, the only memorable part of the movie namechecked in this episode.

One of my favorite moments in the episode was its second best joke (after “Derby, Lincoln, THE WORLD”): the Doctor, chained to a post and bickering with Robin Hood about their relative prowess, insists correctly that of the two of them he would be better at “dying more slowly.”

The other is of course the end, where we think someone’s describing Robin Hood and it turns out they’re describing the Doctor, also a man of privilege who fled that role in order to help those less fortunate, also larger as a story than as a man, and the more powerful and wonderful for it.

The robot design is excellent; whoever’s responsible for it and for the clockwork robots in “Deep Breath” is really knocking it out of the park this season. It’s interesting, this connection between robots, cross imagery, and the “Promised Land” motif. No doubt some wag has already speculated that we’ll see Kamelion there by season’s end.