Project Hail Mary

The Most Fun Science Fiction Has Had in Years

Andy Weir made his reputation with The Martian (2011) — the story of Mark Watney, an astronaut stranded on Mars who applies science to stay alive, one problem at a time. Project Hail Mary takes everything Weir does well and does it better.

This is a novel about a man alone in space with a potentially world-ending problem, unlimited scientific curiosity, and — eventually — an extremely surprising companion. It is the best science fiction novel of the 2020s.

The Setup

Ryland Grace wakes up in a spacecraft with no memory of who he is or why he’s there. Two crewmates float dead beside him. He is millions of miles from Earth.

The first third of the novel unfolds as a mystery: Grace recovers his memories in fragments while figuring out the spacecraft, the mission, and what went wrong. Weir uses this amnesia structure brilliantly — the reader and Grace discover the situation together, and the revelations escalate exactly as needed to keep the tension high.

What Grace gradually remembers: the Sun is dying. A microorganism called Astrophage is consuming solar energy and spreading from star to star. Within decades, Earth will freeze. The Hail Mary — a one-way mission to the Tau Ceti system, the only star in the region not losing energy — is humanity’s last attempt to understand why and find a solution. Grace was not the first choice for the mission.

The Science

Weir is famous for the accuracy of his science, and Project Hail Mary is his most ambitious exercise in hard science fiction. The physics of the spacecraft’s propulsion system is real (though speculative). The biology of Astrophage, a fictional microorganism, is designed with careful internal consistency. Grace’s problem-solving methodology — observe, hypothesise, test, iterate — is recognisable science.

Weir has a gift for making complex science accessible without dumbing it down. Grace — a former research scientist turned middle-school science teacher, a backstory that turns out to matter — explains photosynthesis, stellar energy budgets, xenobiology, relativity, and orbital mechanics with a teacher’s instinct for the right analogy and the right moment of wonder. The novel is structured as a relay of self-contained puzzles: each chapter poses a concrete, often lethal problem, and the pleasure lies in watching Grace reason his way out with whatever materials are at hand. It is the purest expression of the “competence porn” Weir pioneered in The Martian, and it never flags.

The Mission Behind the Mission

Interleaved with the present-day survival story are flashbacks to Earth’s frantic response to the Astrophage crisis, anchored by Eva Stratt, the ruthlessly pragmatic administrator granted near-unlimited authority to mount the Hail Mary project. These chapters give the book its scale and its stakes — a planet uniting, and compromising, against extinction — while explaining, piece by amnesiac piece, exactly how an ordinary teacher ended up as humanity’s unlikely last hope. The gradual convergence of the two timelines is part of the novel’s clockwork satisfaction.

Rocky

The central relationship of the novel — which emerges around a third of the way in — is the single best thing Weir has ever written, and one of the most original relationships in recent science fiction. To say much would spoil it, and the discovery is a genuine joy.

What can be said: Grace is not as alone as he thinks, and the friendship that develops is built across a seemingly unbridgeable barrier through patience, shared logic, and the slow construction of a common language. The xenolinguistic problem-solving — two intelligences from incompatible biologies working out how to talk, trust, and ultimately rely on each other — is both scientifically ingenious and deeply moving. By the end of the book you may be more invested than you expected in the fate of a character who is not human, and the warmth of that bond is what lifts Project Hail Mary above mere clever engineering.

A Few Caveats

The novel is not for every reader. Grace’s voice is relentlessly upbeat — all exclamation points and giddy “Fascinating!” enthusiasm — which delights many and grates on some over 400-plus pages. The amnesia framing demands a little patience in the opening chapters, and a key reveal in the second half strikes a minority of readers as a touch too convenient. But these are quibbles against a book engineered, like its hero, to solve the problem of keeping you turning pages.

The Ending

Project Hail Mary ends perfectly. Not a twist, not a reveal — just a quiet, earned resolution that honours every theme the book has developed. It is the kind of ending that makes you sit with the book for a moment before you put it down.

In an era of trilogy setups and franchise-building, Weir wrote a complete, self-contained novel with an ending that doesn’t require a sequel. Rare and valuable. A big-budget film adaptation directed by Phil Lord and Christopher Miller, with Ryan Gosling as Ryland Grace, is bringing the story to the screen in 2026 — but, as with The Martian, the novel’s interior voice and its escalating chain of scientific puzzles are pleasures the page will always keep for itself.

Our rating: 4.8/5 — The most enjoyable science fiction novel of the decade. Start it on a weekend; you will not stop.

Reading Guides

• Books Like Project Hail Mary: 11 Science Fiction Novels for Problem-Solvers
• Books Like The Martian: Problem-Solving, Survival, and Optimistic Science Fiction
• Andy Weir Books in Order: The Martian, Project Hail Mary, and Complete Guide (2026)
• Best Science Fiction Books of All Time — The Essential Reading List
• 25 Best Audiobooks of All Time (Across Every Genre)
• 20 Best Books to Read on a Plane (That You Won