After a hiatus of more than two and a half years, Jay Foreman and Mark Cooper-Jones are back to producing new episodes of Map Men. Back in 2016 I called the series “two silly people being very smart about often-silly cartographical situations” (though I may have gotten that backward). Anyway, they’re back, with episodes on the geological origins of the English-Scottish border and trap streets.

THE DOCTOR: But if the stories are true though, there should be a street in one of these old maps that no longer exists in the real world.

CLARA: Like a trap street, only not.

THE DOCTOR: What did you say?

CLARA: A trap street. You know, when someone’s making a map—a, um, cartographer—uses a fake street throws it into the mix, names it after one of his kids or whatever, then, if the fake street—the trap street—ever shows up on someone else’s map they know their work’s been stolen. Clever, right?

THE DOCTOR: My God! A whole London street just up and disappeared and you lot assume it’s a copyright infringement.

Unlike trap streets, the street exists, and the reason it has disappeared has nothing to do with cartographic copyright. Finding the street takes some doing, as this clip the BBC has made available recently shows; unfortunately, it takes place immediately after the bit I quoted above.