The Castaways ending explained: How does Sheridan Smith shipwreck thriller conclude?

But that’s exactly what poor Lori (Sheridan Smith) finds herself in the middle of in The Castaways.

After falling out with sister Erin (Celine Buckens), Lori lands in a nightmare after heading off to Fiji alone when Erin fails to turn up for the flight, crashing on a desert island with the few survivors all bearing killer secrets.

In The Castaways, nothing is as it seems, with Lori fighting to survive against the elements while the outside world brushes off the crash as an engine failure that killed off everyone on board as it crashed into the ocean. It’s only Erin’s firm belief that her sister has survived that provides any kind of hope.

So was Erin finally able to track Lori down? What caused the plane to crash in the first place? And how many people get off the beach alive?

Here’s how the final episode plays out.

Why did the plane crash in The Castaways?

In the immediate aftermath of the plane crash, authorities chalk it down to the storm it was flying in causing an engine failure. Everyone, apart from Erin, thinks the plane landed in the sea, with everyone killed on board.

But the truth is actually far more deceitful, with pilot Mike Brass (Brendan Cowell) deliberately taking the plane off course as part of a plan to appease a rich man trying to bump off his mistress, who was threatening to expose their affair to his wife.

The plan was to divert the plane due to a seeming issue with the engine, forcing it to land elsewhere. The man would then kill his mistress during the downtime as the plane was ‘fixed’, lie about ever knowing her, thereby leaving his hands clean by the time they get back on board.

Things didn’t quite work out that way though. Due to the storm, which they weren’t expecting, the plane crashed for real, killing everyone on board apart from a handful of survivors – including Lori, pilot Mike, Daniel (Dominic Tighe), Felix (Lasarus Ratuere), Jack (Joseph Mydell), Amber (Charlotte Vega) and her baby, Sonny. Amber was badly injured in the crash, causing the group to rally around her and her son to keep them alive.

It takes a while, but it emerges that Amber is the ‘other woman’ and the baby is the result of her affair with Daniel. Daniel is therefore responsible for their dreadful predicament and, to make things worse, he still intends to go through with it.

Mike, intent to save his own skin, later flees the island on a raft they create, giving himself a new identity and living in Fiji undetected, not even telling anyone there are survivors.

But after using Lori’s credit card, Erin sees this as her shot, and manages to track him down. He confesses everything, including his pay off, and she blackmails him to getting on a boat and taking her to the island.

What did Lori and Erin fight about?

Throughout the series, it becomes clear Erin is holding a lot of guilt regarding Lori. At first it seems it’s her guilt about missing the flight to Fiji, but later it’s teased that it’s more than that, with the pair having an “argument they can’t come back from”.

It’s not until the final episode that it’s revealed Lori and Erin, who had relied on each other for years after the death of their parents, had a major fight when Lori discovered her husband, Pete, had been having an affair. To add insult to injury, Erin had known about it, but kept quiet in the hope Pete would come clean on his own.

Feeling utterly betrayed by both Pete and Erin, Lori lets out years of pent-up anger at her sister, tired of being a de facto mother figure for her little sister and even blaming her for not having children of her own despite wanting them.

The comment makes Erin storm out of the restaurant they were in, and it was their last conversation before the tragedy-bound Fiji flight. So Erin’s search for Lori is in part because of guilt over missing the flight, but also because she’s desperate to apologise and repair her once close bond with her sister.

How did The Castaways end?

By the time we reach the final episode, a lot of the remaining survivors are dead. Jack, following the death of his love Heather, decides to end his own life in a bid to join her, and save resources for those who actually want to stay alive. This devastates Lori, who takes on a leadership role within the group.

Lori, who has started falling for fellow survivor Felix, has been determined for answers, but almost died herself when she felt like all hope was lost at their discovery. Felix saved her, and together they formed an unbreakable romantic bond.

Amber, who had sabotaged their one chance at escape in order to keep her “family unit” dream with Daniel and Sonny alive, later goes missing, with Lori discovering the truth about their relationship and assuming Daniel had killed her.

Mike is also dead, having been shot by a woman who had been tasked by Daniel’s wife to find him. Before he does so, he reveals he is the reason Erin missed her plane, having bonded with her the night before the flight and stealing her phone to ensure she missed it.

So tensions have reached their peak by the time the finale comes around, with Erin and Lori finally reunited and deciding to get baby Sonny to safety – but Daniel isn’t willing to let his son go that easily.

The sisters both trick Daniel, with Lori pretending to be on his side, and Erin pretending to be someone working for his wife, who knows about his affair, and has laid plans to get him to safety. Commanding him to get rid of any evidence of what happened before they board the boat, he willingly does so, and the girls flee with the baby.

But Lori isn’t willing to leave Felix behind, and returns to try and find him. With a showdown on the beach, the sisters end up killing Daniel, just as a police boat makes its way towards the island.

Felix, who is on the run anyway, decides not to return to the mainland, preferring to live his days in this survivalist world he has grown accustomed to. While she initially leaves him, Lori realises she’s in love with him, and in a tearjerking moment, the sisters reconcile and decide to let each other go, allowing Lori to live the life she wants for once.

As the series comes to a close, Erin is grilled about what happened on the island, but the police’s bungled investigation on the crash leaves them with nothing to go off. She ensures that Sonny is sent to a loving home, tells everyone Lori is dead, and gives the cash Mike got from the plane crash to his estranged daughter.

In the final moments, it appears everyone has got their happy ending, with Lori being seen smiling on the beach, fishing and finally pregnant with the baby she’s always wanted, while Felix builds them a fire nearby.

The Castaways airs on Channel 5 and is available to stream on Paramount Plus – get a seven day free Paramount Plus trial at Amazon Prime Video.

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