Breaking Down the Ending of ‘Project Hail Mary’

Grace really didn’t volunteer for this, huh?

The synonym for bittersweet that best describes the ending of Project Hail Mary hasn’t been invented yet. Or maybe it’s in an alien language that can’t be properly translated. Here are the key takeaways from the end of the film. If you want to learn even more, especially when it comes to all of the science involved, you can always read the Andy Weir novel the movie is based on.

Ryan Gosling stars as a scientist who wakes up in outer space with a mission to save the Earth from a dying sun, but no memory of how he got there and why. He was in a coma for the interstellar journey and, you know, sh*t happens. Unfortunately, the two other members of his crew are dead when he wakes up. When he arrives at his destination, he makes first contact with an alien he names Rocky (James Ortiz) from a planet named Erid that sent him on the same mission. Once the two of them learn how to communicate with each other, they start to work on a solution for the problem.

Nope! Through flashbacks, the film reveals the circumstances under which Ryland Grace (Gosling) ended up on the Hail Mary spaceship mission in the first place. Because of that, we got that big moment where the protagonist insists he’s the wrong guy to save the world at the end of the movie instead of the beginning–shout out to everyone who read Joseph Campbell’s The Hero with a Thousand Faces in high school. They flipped it!

As one of the last flashbacks reveals, Grace never really accepted the call to action. He refused, and his commander Eva Stratt (Sandra Hüller) had him drugged and induced into a coma. She was right to do it, because he was kind of the only person with the right skillset, but it was brutal. Weirdly, this might have actually saved his life. We don’t know why the other two crew members died. But Grace doesn’t really remember that until the end of the movie, which makes his sacrifices all the more heroic.

Jonathan Olley

Did they save the Sun?

Let’s back up and briefly summarize the central conflict: little black dot lookin’ aliens called astrophage are eating the sun and other nearby stars. They’re single-celled organisms, but super dangerous for life on Earth. Grace, a middle school science teacher who used to be a radical molecular biologist back in the day, discovers that the astrophage are traveling to and from Venus to breed. Other scientists on Earth have determined that one star in the vicinity, called Tau Ceti, seems unaffected by the astrophage. The only way to potentially save the sun and Earth is to go to that star and its nearby planet and investigate why astrolage leaves it alone.

That’s where Grace and Rocky meet. Eventually, the two of them go down to the surface of the Tau Ceti-E, a.k.a. Planet Adrian, to collect a sample and run experiments on it. Grace discovers that the planet hosts a predator species that can kill the little dot aliens. He names the predator “taumoeba” and sends samples and instructions on how to breed them back to Earth in a probe.

In short, yes! We learn at the end of the movie that the mission was successful and Earth’s sun has been restored to its former brightness. Erid is safe as well. They did it.

It’s kind of crazy to me that nobody considers how they’re basically starting a war between two microbial alien species without their consent. I’m not saying that I wouldn’t do the same thing to save humanity. It’s no different than creating a vaccine to treat a disease, or getting a cat to deal with a mouse problem. Right? Still, I would at least pose the ethical question just to have it on record.

Jonathan Olley

OK, but, does Grace get to go home to Earth?

Initially, the Project Hail Mary mission was meant to be a one way trip. Earth’s scientists didn’t have enough fuel to send a crew to Tau Ceti and back. So the plan was for all three of them to die in space, and sacrifice their lives for the greater good of humanity. They had enough food and supplies to live in space for about a decade, and then give themselves a lethal injection when they were ready to go.

Grace, again, did not volunteer for that fate. When Rocky learns about this plan, he’s not happy either. He offers to lend Grace enough fuel from his ship to get home.

Problem solved? Not quite. Both of their ships are also using astrolage as fuel. Wouldn’t you know it, the astrolage-eating predator that’s going to save the universe is also eating the fuel, as well as damaging xenonite a.k.a. the material that Rocky’s ship and Rocky himself are made out of. Grace discovers this and decides to turn back around to save Rocky’s ship from leaking and killing him. You really can have it all: heroics and friendship. It just means that Grace can’t go home as they planned.

Instead, Grace takes Rocky back to Planet Erid with him in the Hail Mary. That’s where he ends up at the end of the film. Rocky’s species build a biodome for him where he can breathe, eat, walk around, and even chill out on a beach. They hire him as a science teacher, too. It’s kind of an ideal gig. Rocky tells him that Eridian scientists have fixed his spaceship up so that he can return to Earth if he wants to. But honestly? He’s in no rush. Given the hostile way he left the planet, I’m not sure I would be either.

How much time passed during Project Hail Mary?

This was on my mind during the film, so let’s crunch some numbers. When Grace left, scientists estimated that they had 30 years to fix the sun before at least 25 percent of the world’s population died. The journey to Tau Ceti, during which Grace was in a coma, was four or five years from his body’s perspective. But he was traveling close to the speed of light. Because of time relativity laws that I am not qualified to explain, and basically only understand because of science fiction movies like Interstellar, a whopping 13 years passed on Earth just for that initial space voyage.

So, if it took 13 years on Earth for Grace to reach Tau Ceti, many months if not a couple of years for him and Rocky to work out a solution to the astrolage problem, and then another 13 years for the probes to send Grace and Rocky’s findings and the taumoeba back to Earth, that’s at least 27-28 years. They made it right under the wire!