Prepare for liftoff: Project Hail Mary, one of the first blockbusters of 2026, has officially touched down in theaters.
Based Andy Weir’s 2021 bestseller, the sci-fi epic follows overqualified middle school science teacher–turned–astronaut Ryland Grace (Ryan Gosling) as he travels to another galaxy in a last-ditch attempt to save Earth from an alien microorganism devouring the sun — forming an unlikely friendship along the way.
As with any book-to-movie adaptation, two key questions come to mind: How does the Phil Lord- and Chris Miller-helmed film compare to its riveting source material, and does it stick the same landing?
Let’s break it all down below this conveniently placed spoiler warning:
SPOILER WARNING: The rest of this article contains major spoilers for both the book and screen adaptation of Project Hail Mary. You have been warned!
Project Hail Mary Ending Explained
Lovers of the book, rejoice: Project Hail Mary is an exceptionally faithful adaptation of Weir’s novel.
The author’s narrative was masterfully brought to life by esteemed screenwriter Drew Goddard, who also wrote the screenplay for the adaptation of Weir’s The Martian (2015), starring Matt Damon.
While some plotlines were streamlined — and some science was simplified — for focus and clarity, Goddard, along with Lord and Miller, skillfully captured the key story elements, sharp humor, and profound emotional gravity of Weir’s interstellar odyssey.
That, of course, meant preserving the novel’s poignant ending — save for a few minor tweaks.
As seen in the book, Ryland Grace (Ryan Gosling) sacrifices his chance to return to Earth to save his alien best friend Rocky (James Ortiz), ultimately choosing to stick around on his pal’s homeworld of Erid.
Upon learning that Rocky’s ship was damaged, Grace sends the Hail Mary’s beetle probes back to Earth — containing instructions on how to breed the Astrophage-eating Taumoeba — before flipping the ship around and catching up to Rocky, saving both planets in the process.
The film’s epilogue picks up years later on Erid, though a much shorter time has passed in the movie than in the book. The Eridians have built Grace a massive, specialized habitat, complete with a sandy beach — far more impressive than his humble enclosure from the novel.
Still, both versions end with Grace finding purpose in returning to his typical 9-to-5: teaching science to young Eridians.
Here’s where the film briefly takes a more noteworthy turn.
In the novel, Grace is informed that the sun’s luminosity has been restored, meaning the beetles have returned to Earth and the planet has been saved. But since the narrative is largely told from Grace’s perspective, readers never learn exactly what happened to Earth during the mission—or the fate of project director Eva Stratt (Sandra Huller).
In the film, Goddard chose to quickly shift focus back to Earth through the POV of an older Stratt, who is seen traversing through a frozen ocean, the result of global cooling from the sun’s dimming. Stratt is in possession of the beetles and reacting to Grace’s video log with Rocky — another addition for the movie — gearing up to launch the next phase of humanity’s recovery effort.
Stratt’s epilogue only enhances the source material, reinforcing the novel’s optimistic message and providing meaningful closure to one of the film’s central characters.
Project Hail Mary FAQs
When does Project Hail Mary come out in theaters?
Project Hail Mary is being released in theaters nationwide on Friday, March 20th.
What is Project Hail Mary based on?
Project Hail Mary is based on the 2021 sci-fi novel of the same name by Andy Weir, who also wrote The Martian (2011) and Artemis (2017).
Who stars in Project Hail Mary?
Ryan Gosling stars in Project Hail Mary, alongside Sandra Huller. The film’s alien character, Rocky, is voiced and puppeteered by James Ortiz.
