The Vault ending explained: Who is the traitor?

When Balagueró's film was finally released, it opened with €1.2 million on its first weekend, becoming the biggest Spanish box-office debut of the year (up until that point).

But where The Vault would find its biggest success would be later on Netflix, where an even larger audience could check out Highmore's big score and crack the code of that one big twist at the end.

Read on to have the ending of The Vault broken down.

The Vault ending explained: Who is the traitor?

During the 2010 Spain World Cup, an English graduate named Thom (Highmore) joins a gang of thieves who plan to hit a vault and steal back some treasure from the Bank of Spain, which should lead them an even bigger haul elsewhere. Thom's engineering expertise will prove to be invaluable, especially when it comes to cracking the titular vault, a centuries old technological marvel.

And yes, that World Cup setting will turn out to be somewhat relevant. Trust us.

The crew, assembled by an enigmatic treasure hunter named Walter, have already prepped everything else they need, including the keys and fingerprints required to open the vault. The problem is that once they go inside, any change in weight will instantly flood the chamber, drowning any pesky thieves stupid enough to actually try and break in.

The Bank of Spain actually uses a similar contraption in real life, as also seen in Money Heist season 3, but that doesn't help our fictional Thom, who must figure out a way to disable the mechanism long enough for everyone to survive.

Thankfully, the solution comes to him in a cocktail glass, as so many answers often do.

During a night out with a fellow thief, Lorraine (Àstrid Bergès-Frisbey), Thom sees a nitrogen cocktail being made and figures out that liquid nitrogen could be used to freeze the scale in the vault, so a change in weight would no longer matter. That means the gang can infiltrate the vault with peace of mind, which is exactly what they do, nabbing the coins they needed all along. But no heist goes off without a hitch, and in this case, the problem is that the nitrogen ends up thawing quicker than Thom predicted.

The alarms go off then and the chamber floods, which is not exactly ideal. In fact, it's the one thing the gang didn't want to happen, although the nitrogen did buy them some time at least.

James (Sam Riley) is the only one who can easily swim out thanks to his military training. Yay! But then he reveals himself to be a former MI6 operative and goes on to betray them all for the Crown.

Holding the others at gunpoint, James escapes with what he believes are the real coins. To survive, Thom then asks Simon (Luis Tosar) to place the nitrogen canisters on the bottom of the scale to trick it and reset the mechanism.

As the water recedes, Thom and Lorraine make it out of the vents and slip into the bustling crowds outside who are cheering for Spain in the World Cup. The bank's head of security, Gustavo Medina (José Coronado), orders his men to shoot at them, but they can't without risking an innocent bystander getting hurt.

Thom and Lorraine share a kiss in the heat of the moment before they manage to slip away amidst the cheering fans when Spain scores a goal.

Why are they so happy when they've lost the coins they've been hunting for all this time?

Well, when James reports back to his superior, Margaret (Famke Janssen), they realise the coins he stole are actually fake. Walter asked Lorraine to swap the coins around beforehand knowing James would double cross them, which means our faves now have the real coins for themselves at last.

Walter uses the treasure to deduce that another bigger prize was hidden by Sir Francis Drake in the Bank of London. So the "treasure" everyone spent this whole film looking for was essentially just a map that will lead them to an even bigger prize, thereby setting up a big Anglophile sequel.

Except, that never happened. As it stands, The Vault franchise begins and ends with this one movie, although there's certainly scope for more, especially if the film begins to pick up more fans following its debut on Netflix UK. Now wouldn't that be a twist?

The Vault is now streaming on Netflix – sign up from £4.99 a month. Netflix is also available on Sky Glass and Virgin Media Stream.

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