Netflix's latest series 3 Body Problem has arrived on the streamer, and the sci-fi adaptation has given us a lot to contend with. From theoretical physics to nanofibers to alien civilizations, there's a lot to wrap your head around in the show, which hails from Game of Thrones creators David Benioff and D.B. Weiss and The Terror season 2 showrunner Alexander Woo.
Based on Liu Cixin's novel, the show takes us from present-day Oxford to '60s China (via a turbulent VR universe), as a group of scientists try to make sense of a world that seems to be slowly coming apart at the seams. You'd be forgiven for still having some question marks in your head once the final credits started to roll, but that's where we come in.
We've got everything you need to know about the 3 Body Problem ending, answering all your biggest questions about sophons, Wallfacers, and more. Be warned, though: as you might expect, there are major 3 Body Problem spoilers ahead, so proceed with caution if you haven't finished the show yet and don't want to know what happens!
3 Body Problem ending explained
The season finale opens with a freak car accident, which kills Saul's (Jovan Adepo) one-night stand as she waits for him to call her a cab. Saul is then interviewed by Clarence (Benedict Wong), who thinks the cars were hacked and were meant to target Saul, and he thinks it's linked to Ye's death at the end of episode 7. Clarence takes Saul on a private jet without telling him where they're going, and they end up at the United Nations in New York City.
This is where the Wallfacer project launched. The Wallfacers are a group of people chosen to make plans entirely in their heads in order to keep defense strategies secret from the San-Ti aliens. Saul is chosen as a third Wallfacer, much to his surprise, along with a Chinese general and a Kurdish war hero. Saul, in denial, tries to quit, but is shot at as soon as he leaves the UN building.
Back in the UK, we see that Tatiana's (Marlo Kelly) home has been broken into and she's been gifted a VR helmet. The package is left for her with a note with the San-Ti motto: 'If one of us survives, we all survive.'
Meanwhile, the Staircase Program is about to kick off at Cape Canaveral, Florida, with Wade (Liam Cunningham), Jin (Jess Hong), and a group of other scientists assembling for the launch of the reconnaissance probe – with Will's (Alex Sharp) brain inside. It's incredibly tense, but the first few explosions needed to launch the probe into lightspeed to reach the San-Ti go off without a hitch. That is, until one of the strings on the probe's parachute breaks, and the capsule veers off course. Jin and the rest of the team are crushed: their mission has failed.
We haven't seen Auggie (Eiza González) for a while, and that's because she's in Mexico, trying to forget what happened at the Panama Canal in episode 5. Instead, she's trying to use her inventions for good, and she's employing her nanofiber technology to filter water in a rural village suffering from a dysentery epidemic.
On his way back to England from Cape Canaveral, Wade is contacted by the San-Ti while he's alone on his private jet. They say they're sorry the Staircase Program didn't work out as they wanted to meet Will – and they still want to meet Wade. The San-Ti voice tells him that there will be a place for him when they arrive, as they can see that he's a strong leader. In one of the series' most creepy moments, they tell him that they'll be with him forever and he'll see what they want him to see until the day he dies. Wade then has a vision of the same countdown Auggie saw, then a vision of himself with no eyes.
The episode ends with Jin and Saul drinking at their motel, feeling thoroughly depressed by the failure of the Staircase Program and the terrifying responsibilties of being a Wallfacer. Clarence insists that they jump in the car and go for a ride, though, and he takes them down to a nearby swamp to look at the swarms of bugs. The San-Ti may think humans are bugs, he tells them, but if bugs do one thing, it's survive.
Who are the San-Ti? When are they arriving on Earth?
The San-Ti are the aliens on their way to Earth, who Ye Wenjie first makes contact with from the Chinese military base in the '60s. We later find out that their planet, which is four light-years away, is doomed due to unstable weather conditions caused by the three suns that orbit it (the titular three-body problem). Due to how far they have to travel, they're set to arrive on Earth in 400 years – so around 2424. When Ye first makes contact, it takes four years for sound to travel to the aliens and four to get back, but they have the technology to communicate faster, so instant communication is now possible.
What are sophons?
Based on each species history, the San-Ti have predicted that humans will develop faster than them. By the time the aliens arrive on Earth, humans will have surpassed them, so their plan is to use 'sophons' to try and stop humanity's science and technology from progressing any further. Sophons are extremely tiny computers, and the San-Ti sent two of them to Earth. The sophons can see and hear everything happening on Earth, which is why nothing can be kept secret from the aliens. They can corrupt experiments, like Vera Ye's project, and they can also control reality and what humans see and hear.
What happened to Ye Wenjie?
After the San-Ti learn about humanity's ability to lie, they drop ties with Ye Wenjie (Rosalind Chao), the scientist who first made contact with them, and Mike Evans (Jonathan Pryce), another of their dedicated loyalists. Ye realizes that they've abandoned her and deemed her unimportant when they allow her to be captured and interrogated by Wade's organization. When Clarence releases her after questioning, she travels back to China to the site of the military base where she worked 60 years before. Tatiana is waiting for her – she was sent to kill her by the aliens, but Ye was planning to jump off the cliff anyway, so her fate is sealed.
What happened to Will? Was the Staircase Program successful?
In episode 2, Will is diagnosed with terminal thyroid cancer and given two to six months to live. In episode 5, Wade pitches Operation Staircase, which will involve sending a reconnaissance probe to intercept the San-Ti on their journey to Earth.
With the aliens still being 400 years away, though, how will any kind of spacecraft reach them in time? Well, it's Jin's idea to use nuclear weapons to launch the probe, which will then be propelled by a 'radiation sail' of multiple continuous nuclear explosions and a parachute – by her calculations, 1,000 explosions will be needed to hit the required 0.0112 lightspeed. Wade wants to send a person but, in order to reach that speed, the craft can only carry up to 2kg – so he wants to remove a person's brain and send that instead, with the idea that the San-Ti have the technology to "rebuild" whoever volunteers. Jin suggests Will, as he's already dying, and he agrees.
Will undergoes a procedure to remove his brain from his body, which is then frozen and put into the craft. Wade, Jin, and other scientists travel to Cape Canaveral, Florida, for the launch, and the first few explosions are successful. That is, until one of the parachute strings breaks and the capsule veers off its course. That means Will's brain is left to float in space indefinitely.
Who are the Wallfacers? Why was Saul chosen to join them?
The Wallfacer project is launched in episode 8. Wallfacers are people chosen to fight the San-Ti by making plans entirely in their heads – they can't tell anyone, write anything down, or share their ideas in any way, as the only thing the San-Ti can't do is read minds, so this is the only way to keep defense or attack strategies a secret.
Saul is chosen to be a Wallfacer, along with a Chinese general and a Kurdish war hero. The trio will have the world's resources at their hands and won't be questioned on how they use them, as long as it doesn't violate international law. No one is able to tell Saul why he was selected, even the UN General Secretary – just that the San-Ti think he's important. And just why they think that is a question we'll have to wait until season 2 to answer.
All episodes of 3 Body Problem are streaming now on Netflix. For more on the show, check out our guide to what could happen in a potential season 2 based on the books.
