Black Mirror: Myha'la Herrold and Sam Blenkin were 'appalled' by Loch Henry's ending

Watch: Myha'la Herrold and Sam Blenkin reflect on Loch Henry's big twists.

The cast of Loch Henry were "shocked and appalled" by the unexpected twists in the episode of Black Mirror, which premiered on Netflix on Thursday, 15 June.

Loch Henry follows couple Davis (Sam Blenkin) and Pia (Myha'la Herrold), aspiring documentary filmmakers who travel to Davis' sleepy Scottish town in order to make a film about a man who protects eggs, they decide to switch subject matters though when Pia learns of a series of gruesome murders that took place decades earlier.

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Before we delve any deeper into exact details about the episode, consider this your spoiler warning.

The disappearance of a couple on their honeymoon led to a huge investigation in Davis' hometown, and it was discovered that a local man had kidnapped, tortured and killed them, and countless other tourists.

The investigation inadvertently led to the death of Davis' father after he was shot while on duty, and his mum Janet (Monica Dolan) is still reeling from the loss years later. Except things are not what they seem, and as Davis and Pia dig into the crime more they soon realise that the truth is a little closer to home because Davis' parents were actually involved in the killings.

Speaking of his character's struggle with the revelation, Blenkin says: "I think it drives home the kind of social commentary that Charlie [Brooker]'s talking about in the episodes so succinctly because you instantly put yourself in his shoes.

"You think, 'what would it be like if that happened to me?' So, you know, I was shocked and appalled and also delighted in the way that the episode kind of provokes you. You know what I mean?"

The story doesn't end with Davis' parents being uncovered as fellow killers, though, oh no. This is Black Mirror, so the episode goes one step further.

For one, Pia dies whilst trying to escape Davis' mum after finding out about her role in the killings. His mum then takes her own life rather than face the consequences, but leaves the evidence for her son to find.

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It is then revealed that Davis actually finished making the documentary using footage of the killings that his mum had kept in the house disguised as recordings of Bergerac. He even wins a Bafta for his film, but fame comes at a heavy price as the character is now completely alone in the world.

"I loved the fact that it was so, so ridiculously horrendous, that suddenly their documentary became commercially viable because of that tragedy," Blenkin says.

Herrold, meanwhile, admits she was "shocked" when her character suddenly died: "I was devastated by my untimely demise, I was like 'what the heck?' It was unfortunate, and then the rollout of it all is how it would be [in real life], which is the scariest part, I think."

Blenkin was particularly surprised by the episode showing a trailer for the documentary, adding: "I really liked when it comes back around, it put the existential fear into me, really, then.

"I was like 'oh no!' You sort of realise that the stuff you consume you're not thinking about [what it's like for the victims]. So I thought that was a really clever device, I really liked that."

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Herrold concurred, saying that "even though [she'd] read the script" it still came as a shock to her when she was able to watch the episode.

"I forgot and then remembered, and was like 'oh it's even worse to watch it,'" she admits, telling Blenkin that they'd done a "good job" with bringing the terrifying story to life.

Black Mirror season 6 is out now on Netflix.

Watch the trailer for Black Mirror season 6.