6 huge ways BBC’s The War of the Worlds is different from the book

• The War of the Worlds spoiler-free preview: “A solid and interesting adaptation”

So, with that in mind, viewers can expect the drama to stick closely to the original source material, right? Not exactly.

“It's not massively faithful, to be honest,” show writer Peter Harness told RadioTimes.com and other publications on set. “The spirit of it is what I've tried to be faithful to. But I also wanted to make it new and feel as though it's unexpected.”

In other words, fans of the original book may notice plenty of changes from the source material. Such as...

1. The show’s male lead actually has a name

Specifically, George – the journalist played by Rafe Spall. George is a character based on the narrator of the original book, a man who remains nameless throughout the entire story. And he’s not the only one: all of the main characters – aside from Ogilvy (the astronomer played by Robert Carlyle in the TV series) ­­– aren’t named in the novel.

While George is imagined as a struggling newspaper writer in the TV show, the narrator of the original text only briefly describes himself as a “professed and recognized writer on philosophical themes”. And that’s basically as much as we learn about him, with the book focusing on action and events rather than any characterisation.

“The book is more like a piece of reportage similar to a piece of journalism,” explains Harness. “The original text touches on the mental state of the characters but it doesn’t really go very deep into them. The challenge [with the TV show] was to build the architecture of a character drama underneath the larger set pieces and big moments within the story.”

2. Eleanor Tomlinson’s character has a much bigger role

In fact, Amy arguably doesn’t exist in the book. While the narrator does have a partner in HG Wells’ story, he drops her off at Leatherhead soon after the Martians land, only reuniting with her at the story’s end. And she’s the most noteworthy woman in the entire book.

“That’s the biggest thing I wanted to do with the story: give it a female lead,” says Harness. “Amy is much more of an action character than George. She's more capable of dealing with the world as it changes. And he's much more sensitive.”

3. The Martian ships have dropped their steampunk look

In the show, the Martians make their grand entrance in a mysterious giant circular orb (not unlike the spherical void ship the Daleks used in Doctor Who). And, when they start their killing spree, the aliens roam the Earth on gigantic far-from-steampunk futuristic walkers.

It’s a huge change from the original book, in which the aliens land in a metallic hollow “cylinder” before terrorising the planet on deadly tripods described by Wells as “boilers on stilts”.

Why the swap? As Peter Harness explains, it was essential to making the aliens scary to modern audiences.

“When [The War of the Worlds originally] came out, that must have been what people who were looking at alien civilisations were expecting.

“But nowadays, that [look] has a different resonance. That’s steampunk, and it almost takes it into a more arch 'knowing genre' way of doing it, which would make a statement about the story that perhaps I didn’t want to make – that it’s somehow nostalgic or cosy.

“I think, really, the important thing with those aliens was to make them unknowable and incomprehensible and terrifying.”

He added: “I just think we tried to give the Martians their own kind of technology, which we discussed as being more crystalline, and organic, and able to grow and regenerate. Which is maybe more in keeping with what we’re thinking about in terms of nanotechnology today.”

4. The Martians don’t venture outside their landing craft

After episode one of The War of the Worlds you may have been asking one big question: where actually are the Martians?

Although the tripods and mysterious landing craft were seen rampaging across Edwardian surrey, the actual aliens themselves weren’t visible. However, in HG Wells’ original novel, the Martians make an appearance pretty early on.

In the book, the narrator witnesses the aliens ­­– monsters described as bear-sized creatures with “V-shaped mouths” and "Gorgon groups of tentacles" – exit their landing craft soon after touchdown. But they hardly enjoy a friendly meet-and-greet with the onlooking humans. Crippled by the “heaviness” of Earth’s gravity, the aliens struggle to make simple movements and are left gasping by the “strange atmosphere”.

It’s only after the humans initially flee and return carrying a white flag that the Martians unleash their deadly “heat ray”.

5. The Martian invasion is given a date. Sort of.

Remember when we said that the setting of this new adaptation is faithful to the original book? Well, the novel doesn’t actually indicate exactly when the invasion happens.

Although the characters, technology and vehicles described in the original novel suggest the action takes place around when the book was first published (1897), a precise date isn’t given.

The BBC adaptation, however, gives audiences a much better idea. According to news reports referenced in the show, the Martians arrive on the verge of the Russo-Japanese war, placing the drama in late 1903 or early 1904.

Why add this detail? Harness argues that a passage in the original book describing a sequence of ‘oppositions’ (when Mars and the sun are on directly opposite sides of Earth) suggests HG Wells also set his story at the same time.

“Looking at it, I think Wells is actually setting the book in about 1904-ish. He's setting it just slightly in the future,” he said.

“That may be me projecting onto it, but I do genuinely think that he was nudging it slightly into the 20th century. So that's why I made that decision to set it then.”

6. ‘The Red World’

The drama’s first episode features ominous scenes of hooded figures moving across the surface of a dusty red landscape. However, as we find out at the end of the first episode, this red world isn’t Mars at all, but a future image on Earth. Those hooded figures are actually Amy and her and George’s son, now several years old.

This doesn’t just represent an interesting twist, but a huge divergence from the book. While the Martian invasion does threaten to wipe out the human race, it only lasts several weeks. As Amy was only in the early stages of pregnancy during the first Martian landing, clearly the alien onslaught will last for many years in the drama.

Well, assuming it stops at some point, anyway.

The War of The Worlds airs 9pm on Sundays at BBC One