Project Hail Mary

When Ryland Grace wakes up, he doesn’t remember who he is, where he is, or what he’s doing. All he knows is that he’s strapped to a bed in a sterile room, attended by a robotic medical arm. Nearby are two corpses — crewmates who didn’t survive. Slowly, his memories trickle back like distant echoes.

He learns that his name is Ryland Grace, and that he’s aboard a spaceship traveling through deep space. The ship is called the Hail Mary. And then he remembers the mission: he’s humanity’s last hope.

Years earlier, scientists on Earth discovered a terrifying phenomenon. The sun’s energy output was decreasing at an alarming rate. After much research, the cause was identified: a mysterious, spacefaring microbe that feeds on stellar energy. It was dubbed astrophage. The implications were catastrophic — within decades, Earth would be too cold to support life.

But a small ray of hope emerged. While most nearby stars were also dimming due to astrophage, one — Tau Ceti — was not. A multinational coalition formed to investigate. If Tau Ceti had astrophage but wasn’t dimming, something must be protecting it. Something humanity could use.

Thus was born Project Hail Mary: a one-way mission to Tau Ceti to discover how that star is surviving, and to return the solution to Earth — if possible. Grace had never intended to be part of the crew. He had been a scientist — a molecular biologist turned middle-school teacher after a career-ending academic dispute. But when the original crew succumbed to coma-related complications, and with time running out, Grace was chosen as a reluctant last resort. He had the knowledge. He could fly solo. He just didn’t agree to it consciously — he was sedated and loaded into the ship against his will.

Now, 12 light-years from Earth, Grace must piece together clues, alone, to save humanity.

The Hail Mary is powered by astrophage itself, whose energy density is high enough to enable interstellar travel. As Grace explores the star system, he discovers something shocking: he’s not alone.

Another ship is nearby — massive, alien in design. Soon, first contact is made. From the alien ship emerges a creature like nothing on Earth: spider-like, five-limbed, encased in rock-like armor, breathing ammonia and communicating through musical tones. Grace names him Rocky.

Despite their biological differences, Rocky and Grace find common ground: both their worlds are dying because of astrophage. Rocky’s species, the Eridians, live in the 40 Eridani system and have advanced technology but are as desperate as Earth. The two form a working partnership — and a deep friendship.

Together, they investigate Tau Ceti and discover the key to its resistance: a natural predator of astrophage, a microbe they name Taumoeba. It exists only in this system, but it eats astrophage, keeping the star clear. The problem? Taumoeba is fragile — it dies quickly under any conditions outside of Tau Ceti. It has to be engineered to survive on both Earth and Erid.

For weeks, Grace and Rocky work tirelessly. They share data, invent joint experiments, and modify Taumoeba to become more resilient. They face setback after setback, but their trust in each other grows. Grace begins to care more for Rocky than he ever expected — not just an alien colleague, but a friend.

Eventually, success. A hardy strain of Taumoeba is developed, capable of withstanding the environments of both planets. Grace prepares to send samples back to Earth using a preprogrammed probe. Rocky, too, prepares to return home. Their mission is nearly complete.

But tragedy strikes.

A breach in Rocky’s ship threatens his life. The ammonia atmosphere he requires is leaking, and he’ll die without repairs. Grace faces an impossible choice: continue on the Hail Mary’s programmed course and return to Earth a hero — or turn back, save Rocky, and risk being stranded light-years from home.

To Grace, the choice becomes clear. He turns the ship around.

He rescues Rocky and helps rebuild the Eridian ship, but doing so uses up the return fuel. Grace knows he won’t see Earth again. He watches as Rocky flies home, taking the Taumoeba with him. Grace, alone once more, finds solace in knowing he did the right thing.

Time passes.

In a surprising turn, Rocky returns. With advanced Eridian tech and knowledge of human biology, he helps build a livable environment for Grace on Erid. There, Grace becomes something unexpected: a teacher again. This time, he teaches alien children — the next generation of Eridians — about Earth, humanity, and science.

He’ll never go home. But he saved two worlds. And in that, he finds peace.

Themes & Reflections

At its core, Project Hail Mary is about sacrifice, cooperation, and the quiet heroism of doing the right thing — even when no one will ever know. Grace doesn’t become a hero because he set out to be one. He becomes a hero because, faced with impossible odds, he chose empathy over glory, science over superstition, and friendship over fear.

Through Rocky and Grace, Andy Weir presents an optimistic vision of first contact — not as a war or invasion, but as a partnership built on mutual respect, curiosity, and trust.