It is a week of revelations. Some are interesting, some are not so much. The Skitter’s bipedal, attenuated, sting-ray faced overlords? Interesting. Weaver’s family? Not so much.

Look, people infer things about other people all the time. It is how society works, we infer moods and histories and attitudes from what our peers say, don’t say and imply. So, when Weaver commented a few weeks ago about how harnessed children had been killed by desperate parents trying to free them without knowing how? The viewers realized that he had lost a child that way.

That means you don’t have to spend 15 minutes laying the minutiae of his marriage and misfortunes out for us. We get it, it’s more fun getting it ourselves, in fact, and now you can focus on the aliens. Which is what you do well.

I do like this show, it is considerably better than the torpid Torchwood, but they always seem uncomfortably handling revelations about their human characters. It always turns into an unconvincing blurt of exposition. The drip of Skitter related information and developments, on the other hand, has been close to perfectly dealt with.

Enough hints to let the audience discern where the story is going, but not enough to remove all doubt.

The human resistance are marshalling their forces. Four days until their assault on the strange alien structures being constructed in the city. They intend to bring down the structures, hoping they are important to the aliens’ plans. To do so they need explosives.

Problem is, they do

n’t have anyone who knows how to make them. Except for Pope, who rolls his eyes at Colonel Porter for bringing up that time he kidnapped and tried to kill Mason. ‘That was so three weeks ago,’ he drawls.

Despite being a probable-rapist and a generally homicidal little scrote, Pope’s blase attitude to the alien apocalypse and his snarky asides remain the highlight of the human cast. It is also a nice piece of writing that Pope, the least socially acceptable member of the cast, is the one with the most useful dystopian skill set.

The 2nd Mass put those skills to use in building their explosives – leading to a somewhat creepy alliance between Pope and mop-haired Matt – while Mason, Hal and Weaver go to scout out the structure. They discover that the Skitters, as seemed increasingly likely with every episode, aren’t the masterminds behind the invasion. That honour goes to the silvery sting-ray aliens who have appeared around the strange structures.

So what are the Skitters? Back at the school compound, Glass and Lourdes uncover a clue. Already disturbed by the failure of Ben and Rick to absorb the Harness-Spikes still visible in their spine, they run a covert dissection on the Skitter. A green Lourdes – autopsy was second year – comments that the Skitters aren’t that different from humans. That, as the scalpel uncovers the tarnished, jointed carapace of a Harness, is what Glass is afraid of.

So even as Pope, hobbling and gleeful at the centre of everyone’s attention, discovers a way to destroy the mechs, Glass realizes a whole new horror of what the invasion could mean.

‘They don’t want us here,’ a crazy red-haired lady played by Blair Brown (I guess Walter is infectious on Fringe) tells Hal and Mason. She was captured by the aliens and now she sells them information in return for boxes of tea and food. The harnessed girl who brings the food is Karen, still-faced and shadowed by a hulking alien.

‘We take the fight to them,’ Weaver says.

The longer that Falling Skies runs, the more I enjoy the concept behind it. From the dramatic, but initially simple, concept of a successful alien invasion, the show has evolved a complex, subtle mythology around the aliens. With every question that is answered, two more have to be asked. If these strange, silver-metal aliens are the ones in charge, then why do they need scrap metal to construct their weapons and structures? If it takes weeks for the Harnessed to become Skitters, then where did the first Skitters come from? How long have the aliens been on earth?

Is Drew Roy (Hal) any relation to Ted Danson? Because in some lights, with some hair, he kind of looks like him.