The best new science fiction books of September 2025 by authors including Cixin Liu and John Scalzi

There are some sci-fi heavy hitters with new novels out this month, from Cixin Liu and Stephen Baxter to John Scalzi. I’m keen to check out Ian McEwan’s venture to a flooded version of 2119 – a drowned-world trope also taken up by Yume Kitasei in the intriguing-sounding Saltcrop. The late Mason Coile’s tale of disaster in a new Martian colony, Exiles, is also tempting me, as is more time travelling noir from the excellent Nicholas Binge.

We’re taking a more classic route in the New Scientist Book Club this month, checking out Ursula K. Le Guin’s much-admired 1974 novel The Dispossessed. Come read along with us and see how it compares to the best of today’s science fiction. But back to September 2025…

The literary writer turns to science fiction – and not for the first time (who read 2010’s Solar?). In his new novel, we move from 2014, when a great poem is read aloud and then lost, never to be heard again, to 2119, when the UK’s low-lying areas have been submerged. Scholar Tom Metcalfe looks back at the archives of the early 21^st century, marvelling at the possibilities life offered back then. Then he finds a clue that might lead to the “great lost poem”…

Here’s a treat for fans of The Three-Body Problem – the collected short stories of Cixin Liu, which touch on first contact, machine intelligences and cosmological horror. There are 32 in total, and we’re promised everything from solar systems being devoured to planets being turned into spaceships.

The Hearth is the “celestial birthplace” of millions of planets, and humanity arrived there thousands of years ago, spreading itself across these worlds. When an unknown enemy sees the richness of the Hearth and wants to take it for themselves, Commander Ulla Breen must come up with a plan to unite its disparate elements and fight back. Will she also learn why humanity came here in the first place?

In a near-future version of Earth, coastal cities have been flooded by seas filled with mutant fish. We follow sailor Skipper, the youngest of three sisters, who makes a living by skimming plastic from the ocean and reselling it. When she receives a cryptic plea for help from her eldest sister Nora, who is looking for a cure for the world’s failing crops, she and her other sister Carmen set out across the sea – and a dying world – to find her. Kitasei is the author of The Deep Sky and The Stardust Grail, and this sounds great.

In this time travelling police procedural, detective Julia Torgrimsen (good name!) is brought out of retirement to investigate the murder of a billionaire she worked with while undercover. But she finds two bodies – both of which are billionaire Bruno Donaldson… We loved Binge’s last sci-fi thriller Dissolution here at New Scientist, so I’m looking forward to this one.

This is the seventh novel in Scalzi’s Old Man’s War series. There has been peace in interstellar space for a decade, but now the most advanced alien species humanity has ever met is on the verge of war – and Earth is being dragged into the conflict. Gretchen Trujillo, a mid-level bureaucrat, is given a secret mission that could change the future for humans and aliens alike.

Exiles by Mason Coile

I’m very taken by the cover and premise of this new novel from the author of William (which I enjoyed), who sadly died earlier this year. It’s set in 2030, when a human crew arrives to prepare the first colony on Mars, only to find the new base half-destroyed. The three robots sent ahead four years earlier to set it up need to be interrogated – but one of them is missing…

At a remote research station in the desert, Kinsey and her team discover a strange specimen in the sand. When Kinsey breaks quarantine and brings it inside, it soon becomes clear that the thing is looking for a new host.

This sounds to me like it treads the line between horror, science fiction and fantasy – and that’s a line I like to see trodden. Set against a backdrop of eco-anxiety, it follows archaeobotanist Nell as she excavates two bog bodies discovered in a Somerset fen, while her body starts to manifest “her own wildness”.