Devs ending explained: what happened in the final episode?

Luckily, we've provided a few of those answers below...

What is the Devs programme?

Much of the series revolves around the mysterious Devs programme at tech firm Amaya, which is overseen by Amaya's CEO Forest (Nick Offerman). In the early episodes, we're deliberately kept in the dark as to the precise purpose of the programme - although we know from early on that it is significant and highly secretive.

Leading up to the series finale, we learn that Forrest has designed the programme as a means to reconnect with his wife and daughter, who were killed in a car crash for which he partly blames himself. The system is able to see into the past and predict the future - at least, it is able to predict the future up until the events of the series finale, when it claims that Lily and Forest are both bound to die.

In the final episode, Forrest reveals to Lily that the programme is not called Devs, as many believe it to be, but actually Deus (the V is the Roman numeral for U), referring to the Latin word for God. Forrest had built the machine while subscribing to the theory of determinism, rejecting the Many-Worlds interpretation.

What is determinism and the Everett many-worlds theory?

The issue at the heart of Devs is that of the conflict between determinism and the many-worlds theory. Forrest is a staunch believer in determinism, which states that everything, including all human behaviour, is predetermined - in other words we have no free will or control over our actions.

The conflicting many-worlds interpretation, which was first posed by American physicist Hugh Everett, is put forward by Lyndon, an employee at Devs. This theory suggests that for every possible choice that a person makes, the universe splits, creating different worlds with completely different outcomes. Lyndon believes that he can see into not just the past and future using the Devs system but into these other worlds as well - a belief that Forest doesn't share, causing Lyndon's firing from the company.

What happens in the elevator?

In the final episode, Lily arrives at the Devs lab and is shown a projection of the near future by Forest - which shows both of them stepping inside an elevator before Lily shoots Forest dead, ultimately killing them both, since the bullet punctured the elevator's glass walls and caused it to plummet to the ground. Forest explains to Lily that these images they are seeing can not be prevented - they will happen exactly as they are being seen.

However, just as Lily and Forest are getting into the elevator after having seen the footage, Lily throws away the gun - thus proving that Devs did not accurately predict the future and therefore essentially disproving the theory of determinism, and proving the many worlds interpretation. At this point, Devs employee Stewart (Stephen McKinley Henderson), who has grown disgruntled with the programme, takes matters into his own hands and sabotages the elevator, ensuring that Lily and Forest both still die.

Where are Lily and Forrest at the end of the series?

Of course, the show doesn't just end with the deaths of Lily and Forest. Instead, Katie, the chief designer of the Devs system (and also Forest's girlfriend) uses data to reconstruct them and place them both in a simulation inside the Devs system. Forest continues his life from the moment before his wife and daughter were killed, while Lily resumed hers from a point just before the calamitous events of the series - and only they are aware that they are living in a simulation, as Forest explains to Lily as they are reunited towards the end of the episode. Meanwhile in the real world Katie begs a senator to allow her to keep the system on, allowing Lily and Forest to continue to live their lives in the simulation.

What has Alex Garland said about the ending?

If that's all still a little unclear, luckily series creator, writer and director Alex Garland has provided his own explanation for the ending.

Speaking to IndieWire, he said, "It’s to do with a paradox in literal Christian thinking, to do with Adam and Eve, specifically Eve. You have a sense of God who’s fundamentally presented as omniscient, all-knowing, all-powerful. And then you have Eve, who is punished for an act of free will.

"And the problem is: If God is all-knowing and all-powerful, he knew at the moment he created her that this is what he would do. Or Eve has free will, and is being punished for making a bad decision, in which case God is not all knowing and all powerful.

"I say this as an atheist, but I’ve always found it problematic that dissonance is never properly addressed. But you don’t need to know the mind of God for this to be a paradox.

"I would love it if people thought about, ‘Why is this imagery here? What is it about Lily’s actions?’ And then to have a dawning sense of an argument being made.

"The problem with overtly making arguments is that people usually know what they feel about the argument before it’s presented. They’re agreeing with it or they’re disagreeing with it, but there’s no internal sense of being open.”

Hopefully that clear things up a bit –but if not, maybe it's time to go through the series again and REALLY pay attention this time...

Devs is available to view in its entirety on BBC iPlayer