The episode references other Black Mirror events through newspapers and other text; its themes were compared to "Joan Is Awful", which is also about streaming television.

The episode placed around the middle of critics' lists of Black Mirror installments by quality, though most reviews aggregated by Rotten Tomatoes were positive.

Davis McCardle (Samuel Blenkin) visits his childhood home in Loch Henry, Scotland, with his American girlfriend Pia Koreshi (Myha'la Herrold).

They met in a film course and are pursuing Davis's idea for a documentary about an amateur conservationist in Rùm who prevents illegal egg collecting.

Davis introduces Pia to his friend Stuart King (Daniel Portman), who runs the only remaining pub in Loch Henry, the Lochside Inn.

The former tourist haven is run down because, in the 1990s, resident Iain Adair (Tom Crowhurst) made national headlines as a serial killer.

Davis is worried about its local impact, but Stuart believes the film will bring in tourism, and Janet is happy to voice her anger about Adair's responsibility for Kenneth's death.

Stuart is delighted as tourists fill the Lochside Inn and the series wins a BAFTA award that Cezar dedicates to Davis.

[11]: 7:45–8:00 Brooker was inspired by true crime documentaries, noticing how the genre's increasingly cinematic and art house style gave an air of being "somber, serious" and "important".

[11]: 3:30–4:00  He and his wife Konnie Huq had thought about holidaying in Scotland after seeing landscape footage of it in a true crime documentary.

[11]: 6:10–6:45 An April 2023 announcement named Samuel Blenkin, Myha'la Herrold, Daniel Portman, John Hannah, and Monica Dolan as cast members in the sixth series.

[17] Hannah discovered that the episode had more than the "straightforward horror found footage tale" he initially thought it was, as this narrative is deconstructed.

[12] Herrold said the "creepy" and "eerie atmosphere" made Pia's escape from Janet a highlight of the filming process, although she had to contend with midges in the water.

[25] Neil Armstrong of BBC Culture suggested the episode was the most disturbing of the sixth series;[26] critics identified it as a slow-paced mystery fiction with elements of folk horror.

[14] Den of Geek's Louisa Mellor wrote that it was rare for Black Mirror to give clear answers to moral questions, but that "Loch Henry" does so in its portrayal of true crime.

Streaming services such as Netflix and the fictional Streamberry—both mentioned in "Loch Henry"[34]—are also the subject of "Joan Is Awful", in which the title character's life is adapted in real-time into a television programme.

[38][20] "Loch Henry", like "Mazey Day", criticises mass media and sees inquisitive characters led into danger by their profession.

[30] Additionally, the episode makes Easter egg references to other Black Mirror events through newspapers, news tickers and BAFTA-nominated documentaries.

Referenced events include: Michael Smart of "Demon 79" launching his new political party; Cooper of "Playtest" being found dead; auditions for the "Fifteen Million Merits" talent show Hot Shots opening in Australia; and a Waldo sticker on Davis's computer.

[40] Rachel Dodes of Esquire found it guilty of the "torture porn" that it attempts to criticise; Lawson did not believe its message was original.

[43][42] Adi Robertson wrote for The Verge that it makes "fairly mild observations" about true crime, but fans of the genre already understand its moral issues.

Despite finding the twist predictable, Paste's Leila Jordan lauded the "great Black Mirror gut punch at the end".

[29] In contrast, Robertson believed the "deliberately unsatisfying" conclusion was "rushed" and inferior to the plot twist of "White Bear".

[43] Rosenstock, in contrast, praised its focus on "psychological implications" for Davis rather than "cultural commentary", making it a "fascinating, haunting ending".

[40] Rosenstock praised the "nice chemistry" from "Stuart's brashness", "Davis's tentativeness" and "Pia's adventurous attitude", as well as these characters' humour.

[32] Ed Power, writing in The Daily Telegraph, similarly praised Pia's portrayal as "an outwardly kind person with an inner core that's all ambition" and said Blenkin "shines in the final moments" of the story.

[28] Rosenstock said that Dolan manages to give "weird vibes from the beginning" that make sense from a "lonely, grief-stricken widow" but suggest something deeper.