N.B. there might (or might not) be spoilers in this article!

Gridlock has always been one of my favourite Tenth Doctor episodes — not because it sees the unexpected return of the Macra, nor because at the core of it lies the genuine horror of being stuck on a motorway for over twenty years. (Anyone who’s ever driven in Britain knows that traffic jams can often feel never-ending.)

“Everyone goes to the motorway in the end.”

Customer, Gridlock

It’s not because Martha complains (quite rightly) that the Doctor has taken her on a “date” some place he’s already been with his “ex-” –it’s not really a “date” and Rose isn’t exactly his “ex-“, but still … the “rebound” jibe isn’t far off — nor is it the realisation on both the Doctor and Martha’s parts that they’ve become embroiled in New Earth’s latest mess despite barely knowing each other.

It’s not even because Gridlock forms the last part of a loose trilogy featuring the Face of Boe. It’s an impressive feat to convey that such an enduring friendship exists between the Doctor and the Face given they’ve seemingly only known each other five minutes.

All of those things would be reason — big and small — enough to like Gridlock.

No, if I were to put my finger on the main things I’ve always liked about Gridlock, there are two: one, it feels like it could be a New Adventure and that for me, is always going to be a plus point, and two, it’s that Gridlock hints at stories greater than what we see on screen.

There’s the elderly married couple, one of whom’s a car-spotter; there’s the young couple so desperate to get on the motorway they’re willing to resort to kidnapping. Or even the bowler-haired gent, whose reaction when the Doctor points out that the last time he saw Novice Hame she was breeding humans for experimentation is an absolute peach!

And of course there’s the Brannigans, with a particularly wonderful Ardal O’Hanlon as catkind’s Thomas Kincade Brannigan. (Admittedly, I don’t want to imagine how the seemingly human Valerie gives birth to kittens!) What lives have all these people led to get them to this point?

How implausible is it that someone would spend twenty years in a traffic jam without questioning why it’s taking so long?

Nonetheless, this it-all-hints-at-a-greater-story-without-giving-too-much-away is a skill I’ve always admired in writers — Robert Holmes springs to mind as someone particularly adept at it, especially when it comes to matters of Who lore (coughs “Morbius doctors”) — and it’s arguably the best thing about Gridlock.

Well that, and it’s also a lot of fun!