True Detectivehas always been a dark show,Lodam Bhabhi (2024) S02 Part 1 Hindi Web Series but Night Countryreally ups the stakes.

Set in the fictional Alaskan town of Ennis, located "150 miles north of the Arctic Circle", the HBO show opens on Dec. 17 — an important date, we're informed, as it's "the last sunset of the year". The action itself kicks off a few days later, when police chief Liz Danvers (Jodie Foster) arrives at the Tsalal Arctic Research Station to investigate some missing scientists. One of the first things fellow officer Hank Prior (John Hawkes) says to her after she arrives on the scene?

"Just the third day of darkness and it's already getting weird."

But what's the deal with this long night of darkness, anyway? Is it a fictional device, or something that actually exists in real life?

What is "the long night"?

That opening caption about "the last sunset of the year" pretty much says it all. The idea is that Ennis is a town so far north in Alaska that it experiences extreme seasonal versions of night and day. It's essentially a very brutal version of the nights getting longer in winter — only in Ennis, they get solong that residents experience them as one continuous nighttime. The sun doesn't properly rise or set. In the depths of winter, it's dark all the time.

Is "the long night" a real thing?

The short answer is yes. There are a number of very northern and southern places in the world that experience what's commonly known as a Polar Night, which is a period of darkness lasting more than 24 hours. The closer to the Earth's poles you go, the more dramatic this effect is due to the tilt of its axis. There are a number of remote locations where the effect is so extreme that the sun isn't visible in winter for months on end. Svalbard, an archipelago north of Norway, is one of them. Northern Alaska is another.

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"In Barrow, the northernmost village in the state, there is no daylight for 64 days in the heart of the winter," reads the official Alaska government site. "The sun does not rise above the horizon." Barrow, now called by its Iñupiaq name, Utqiagvik,is a little further north than good ol' Ennis is said to be in the show – it's a whopping 350 miles north of the Arctic Circle – but the effect is the same. For weeks at a time in winter, the only hint of the sun that's visible in Utqiagvik is a faint twilight.

True Detective airs Sunday nights on HBO/Max at 9 p.m ET/PT.