Black Mirror: Beyond the Sea ending explained – what did David do?

Standing at 1 hour and 20 minutes, Beyond the Sea is the longest Black Mirror season 6 episode in the bunch, and presents an unforgettable tale of technology and toxic masculinity.

Beyond the Sea stars Aaron Paul Cliff and Josh Hartnett David as astronauts who use robot duplicates back on Earth to visit their loved ones.

However, when their minds transfer to their robotic doubles while they’re in space, it’s not long before disaster strikes and chaos descends on their families’ lives.

If you've watched it and are still struggling to regain composure after what was one epic episode, read on for a breakdown of what happened at the end and what unfolded. But be warned, there are full spoilers for Beyond the Sea ahead - so only scroll on if you've watched it.

Black Mirror: Beyond the Sea ending explained – what did David do?

For much of the episode, you watch on thinking you'll know exactly what will happen. After the tragic murders of David's wife and children at the beginning of the episode, he's doomed to a life in deep space with his replica also having been destroyed by cult leader Kappa (Rory Culkin).

In an act of kindness, Cliff's wife Lana (Kate Mara) suggests allowing David to come back to earth to breath some fresh air and take some time out via Cliff's replica. David accepts the offer, and the first time he goes to Cliff's countryside home, he breaks down crying in Lana's arms.

It seems likely, then, that an affair could be on the cards but, actually, when David returns in Cliff's body multiple times more to complete a painting for the family, he makes an advance on Lana. She pushes him away, saying that he's confusing her while being in her husband's body and, later that day, she tries telling Cliff that she doesn't want David to return anymore after he hit their son.

Cliff says David can come back one last time, so Lana makes her excuses and leaves the house for the day with her son. While David is using Cliff's replica, though, Cliff finds David's drawings in his bunker. They're all of Lana - many of them of her naked and posing. Cliff is angry because David has stated he can only draw from memory, so begins to question whether the two are having an affair.

Cliff calls David back via an onboard alert and asks him about the drawings, but they get into a physical fight after David admits he finds Lana beautiful. David states that Cliff doesn't know what he's got and that Lana is unappreciated, but Cliff says he knows "damn well" what he has.

Once back at home, Lana is confronted by an angry Cliff who questions her about posing for David. She confesses that although Cliff's replica is here, she feels lonely after being put in the house and left to roam around alone. "He didn't touch me, but I wished he did," she says. "For a moment, it felt like my husband was back and he saw that I'm real." The pair embrace, seemingly coming to a silent agreement with one another.

Back in the spaceship, David apologises to Cliff about overstepping the mark and says nothing happened. But then, Cliff says he knows that because Lana wasn't interested. Cliff says Lana feels offended by David's visits and the thought of him returning to apologise "makes her vomit". Cliff continues calling David "arrogant", "a snake", "a conman" before saying that Lana is "mine, for all time".

Clearly upset, we then see David shave his overgrown beard off and he then stands over Cliff in his bunker. Cliff's replica then gets an emergency alert and back on the ship, David says their coolant tubing took a hit, meaning that Cliff has to don his spacesuit and check on it.

Suited up, David then leaves the chamber and gives him the thumbs up. Whilst investigating the problem out in the dark depths of space, Cliff reports back to David that everything's alright but doesn't get a reply. He's stressed as David is silent so rushes back to the door, banging for David to let him in.

The door light eventually turns green as David lets Cliff back in and when Cliff asks where he was, he says simply "Bathroom". David looks stern and blank faced, but when holding the tray with Cliff's belongings, Cliff asks where his tag is. David pulls it out of his pocket slowly and hands it to him.

Cliff runs back to his bunker and plugs in his tag, but when his replica awakes back on earth, he's horrified to see blood covering his hands and blood spatter on his head. As he makes his way through his home, he sees bloody handprints streaked across the walls and breaks down crying in the kitchen as he slowly makes his way inside.

Everything is kept off camera but what we do see is a pool of blood which Cliff cries beside, intimating that the blood is of Lana and his son and that David, using Cliff's replica, has killed them both.

What happened to Cliff in Beyond the Sea?

After finding out what has happened to his family, Cliff returns to the ship. The ending scene is simple as he slowly walks back into the common area he shares with David.

Cliff is crying and David looks as though he has been but is slowly subtly nodding. He sits at the table and as Cliff sobs, David kicks out the chair to Cliff and gestures for him to sit down beside him. The final shot is of the spaceship with Charles Trenet's Le Mer playing in the background.

While the ending obviously leaves the episode on a bit of an open-ended note, it's obvious to see what will happen. With Cliff's replica being the one that's killed his wife and son, it's highly likely that he would be unable to return to earth in the replica, as he'd risk being arrested or risk the replica being switched off altogether.

Both without families and without a reason to return to earth in any replica, Cliff and David are now in the same position of loss and solitude. And while harsh, it seems as though Cliff will have to deal with that in much of the same way that David had to while confined.

Caught up on Black Mirror season 6? Read our episode breakdowns below:

• Joan Is Awful - episode 1 ending explained
• Loch Henry - episode 2 ending explained
• Mazey Day - episode 4 ending explained
• Demon 79 - episode 5 ending explained

Read our interview with Black Mirror creator Charlie Brooker, as well as season 6 stars Salma Hayek, Aaron Paul and Rob Delaney, in the latest issue of Radio Times magazine – out now.

Black Mirror season 6 is streaming now on Netflix. Sign up for Netflix from £4.99 a month. Netflix is also available on Sky Glass and Virgin Media Stream.

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