Old ending explained: What is the twist at the end of the M Night Shyamalan movie?

Though it's based on Pierre Oscar Levy and Frederik Peeters' graphic novel Sandcastle, the film does divert from the source material in quite significant ways. The new ending is one of them, so if you've read Sandcastle you'll still be surprised by how Old wraps things up.

And, if you're still reeling from the horror's climax, we've got you covered with this Old ending explainer. Read on to find out more, but be warned as there are major spoilers ahead for the Old ending.

Old ending explained

Before we get to the ending, let's recap the context: the film begins with several holidaymakers, including a family of four who serve as our protagonists, traveling to an idyllic, secluded beach, on the personal recommendation of the owner of the resort at which they are staying.

After they arrive at the beach, they soon realise that it seems to be having a very strange effect on them – causing them to age at an alarming rate. We also quickly discover that at least one member of each group at the beach has some sort of health issue – ranging from tumours to epilepsy – something which has vital significance later on.

Anyway, one by one, each of the people at the beach is killed off – some whilst trying to escape, some after succumbing to their health issues or old age, and some of them brutally murdered – leaving siblings Trent and Maddox as the only survivors.

The pair seem to have just about given up on escaping when Trent discovers a coded message he had been given by the resort owner's nephew the day before they arrived at the beach. He cracks the code and finds that it says "My uncle doesn't like the coral".

Trent and Maddox then realise that they have to swim out to a clump of coral in the sea, and that this will protect them from the beach's effects – offering them an escape route. They do so, and initially, it looks like they are unsuccessful in their escape – more on this later.

Anyway then comes the first major twist, as we cut to a lab – at which we find the resort's owner. It turns out that he is a medical scientist and that he and his team have been using the beach to carry out various experiments on unwitting participants.

The owner had deliberately selected groups of people with one or more ill person in their ranks, and had given them experimental medicines when they arrived at the hotel – this is what had been in the fancy cocktails we see the guests drink on arrival.

The beach is then used to see how the various illnesses react to the medicines over time, without having to wait several years to test them in real-time. The owner's rationale seems to be that it is worth killing a few people on the beach when you bear in mind how many people could be saved if the medicines turn out to work – as is the case with an experimental epilepsy treatment one of the guests was given.

It is also clear that this is not the first time that this experiment has been carried out – and indeed it seems that the beach has been in use for some time.

What happened to Trent and Maddox in Old?

This being an M Night Shyamalan film, there is still one twist to come: it turns out that Trent and Maddox did escape after all, and not only that, they've been able to inform the authorities of the beach and the sinister way it had been used.

At the beginning of the film, we saw that Trent had a habit of asking random strangers to tell him their name and occupation, and as it happens this saves the day – one of these people was a police officer, and so he is the person Trent immediately seeks out after escaping.

At the end, we see the resort's owner and his various accomplices being escorted away and it seems that the extremely unethical experiment will no longer be allowed to go ahead.

Interestingly, this is a much more hopeful ending than in the original graphic novel – where no one ever escapes the beach. The source material's writer Frederik Peeters previously told CBR News: "I.... have to say that if someone in the book had escaped or survived, we would have been obliged to give an explanation to the mystery. Again, it’s not a thriller; it’s a fable."

Old was released in UK cinemas on Friday 23rd July 2021 and is currently available to watch on Sky Cinema and NOW. Find out more about how to sign up for Sky Cinema here.

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