“When you take characters, and you put them in that environment, as an audience member, it’s going to be interesting,” MacLachlan adds. “If you feel kinship with the characters, you’re connected to the characters, you’re engaged with the characters, you will be on that journey and experience it as they do.

“But that wouldn’t be possible if you didn’t have a level of sophistication in these games that exist now, that have more going on,” MacLachlan says. “We’re entering a new age.”

Fallout is based on the video game created by Tim Cain, whose other credits include The Temple of Elemental Evil (on which he was project lead) and Star Trek: Starfleet Academy (on which he worked as a programmer).

The television series was written by Lisa Joy and Jonathan Nolan, who came to the project off the back of Westworld, with familiarity of gunslinger-inhabited near-apocalyptic environments. Like many similar series, the genre taps into our obsession with the end of the world.

“We like to feel like we can survive, that the race will survive, the species will survive, regardless of what happens,” MacLachlan says. “The potential for something like that to happen gets more and more plausible, given the kind of weaponry we have, and the kind of leadership that is now in place in certain areas of the world.

“It feels tenuous, [so] I think the feeling is, let’s imagine something horrible has happened and yet, humans can still live on and find a way and endure and life will go on,” MacLachlan adds. “In the case of Fallout, which is so much fun, they have a sense of humour. It’s dark humour, it’s gallows humour, but there’s still humour, which makes it liveable.”

MacLachlan is intentionally vague about Hank - who he is, what his motives are - because it is clear he’s a character who undergoes some transformation across the arc of the series. As we meet him, he’s a gentle figure, which somehow reminds us of Edina Monsoon’s great response to the epithet “blessed are the meek for they shall inherit the Earth”: the meek don’t want it.

“Hank has a reason to be what he is at the time that we enter the story,” MacLachlan says. “He is the right man for the job in that environment. It remains to be seen if his environment changes, but I feel that he is more than capable.

“True to all the people that we are going to go on a journey with in Fallout, Hank is a survivor,” MacLachlan adds. “We’ll probably end up questioning his morality somewhere along the way. But all the people that we meet, that we follow, can endure and some surprisingly so.”

And whether Fallout is truly a western might still be the subject of some fiery and entertaining debate. There is a general sense that it is, but that is largely off the presence of “the Ghoul” (Walton Goggins), a mutated gunslinger who emerges as a sinister presence in the story.

“It’s kind of an amalgam in a way because you have … the Navy SEAL side of things with the Brotherhood of Steel, this ‘isn’t life great?’ sensibility from the Vault-dwellers, and the story of the Ghoul and the whole of the western side of things,” MacLachlan says.

“It’s a strange mashup thrown into a sci-fi world, but I don’t think it’s distinctly western,” MacLachlan says. “It’s like a hybrid.”

There could also be a parable of modern-day America in the story, around the division of haves and have-nots and the idea that one group - those with money - emerge perfectly preserved after the apocalypse, while those around them struggle.

“There is definitely a have and have-not kind of reality, although, some of the question is [for] the have-nots, how bad is it? Do you really want to live in a vault for your entire life and never experience life? So maybe there’s a sacrifice there as well.

“The interesting thing comes when you are actually thrown, as Lucy is thrown, into the world of the surface, which is obviously where the survival part comes in,” MacLachlan says. “But have and have-not, which is better? I don’t know.”

Fallout is on Amazon Prime from Friday.

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