True Detective is back, and there are some standards we have come to expect: A gnarly mystery, a pair of captivating detectives at odds, and twists that will leave us drop-jawed and hungry for more. 

Season 4 takes a major departure, as it's the first not written by creator Nic Pizzolatto. Instead, writer/director Issa López (Tigers Are Not Afraid) helms and co-writes this arc of the anthropology series, which is set in rural Alaska during the polar night — meaning daylight is weeks away. 

Episode 1 introduces us to Ennis Police Chief Liz Danvers (Jodie Foster) and her former partner, disgraced trooper Evangeline Navarro (Kali Reis). The pair are thrown together when a local scientific facility, Tsalal Arctic Research Station, is found abandoned, as if the men working there ran off into the endless night without warning. What's become of these men is just the beginning of this season's mystery, which Navarro believes is related to a cold case from her past: the unsolved murder of an Iñupiaq activist named Annie K.

All season long, Mashable will run down the clues. Here's our round of burning questions from episode 1. 

Where are the missing scientists? 

The Ennis police are called when a deliveryman comes to Tsalal Arctic Research Station with provisions and finds the place abandoned. Ferris Bueller's Day Offplays loudly on the television in a loop. A beer and popcorn have been left behind, as have their phones and a sandwich that seems recently made. "It's like they went to take a leak and never came back," Danvers notes as she surveys the scene.  

Runny mayonnaise and smelly, wet laundry suggests they've been gone for at least two days. But where? By episode's end, some of the scientists are found in the ice, frozen solid. What brought them there? 

The research facility is investigating geology, biology, and the impacts of climate change, seeking the origin of life. (Or, as Danvers refers to it, "Oh. That thing.") Could it be some controversial or cursed discovery that led to their disappearance? Or could the tongue found in the kitchen be a clue that this mystery has something to do with the murder of Annie K? 

Who killed Annie K? 

Six years ago, Annie Masu Kowtok (also known as Annie K) was found dead on the edge of the village. She was stabbed 32 times by an unidentified murder weapon that left star-shaped wounds. Her tongue was cut out but not found. After she was dumped, she was kicked until her ribs and teeth broke. Navarro was first on the scene. Working under then-Police Chief Hank Prior (John Hawkes), she became obsessed with the case but couldn't close it. 

Annie had been protesting against the Silver Sky mines and their possible environmental impact, but as the mines provided much-needed employment to Ennis, her activism was far from welcome.

Catching young Peter Prior (Finn Bennett) up on the cold case, Danvers suggests there are too many suspects to crack it. "This one was never going to be solved," she explains. "Ennis killed Annie. This fucking place. No killer was ever going to be found."

Whose tongue was found? 

At the research facility, Danvers notes the tongue belongs to a Native woman, based on the scarring that would come from a traditional practice for prepping nets.

Hearing about the recovered tongue, Navarro assumes it's Annie's. But Annie was murdered six years ago, while this one seems two days rotted by Danvers' estimation. So, is it the tongue of another ill-fated Iñupiaq woman? Or is it Annie's, because (as we learned in season one) "Time is a flat circle"? 

Who is "she"? 

In the cold open, one scared scientist cries out, "She's back!" Then the lights shut off.

Later, Danvers is asleep when a child's voice calls, "Mommy, she's awake." Then in the very next scene, as Navarro comes upon a one-eyed polar bear, a voice hisses over her radio, "She's awake." 

Is this mysterious "she" Annie, perhaps resurrected as a vengeful spirit? That's our working theory. Sure, it'd be a change-up for True Detective to go so explicitly supernatural — but it'd be true to Lopez's work. (See her beautifully surreal horror film Tigers Are Not Afraid, now streaming on Shudder.)

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Why was Hank hiding the Annie K files? 

Some time ago the Ennis police station was flooded, so Hank took some evidence boxes home for safekeeping. But within his crowded home office, Hank's son Prior finds the case files tucked away in a drawer. Prior steals the files so Hank won't know that they're missing. Why don't Prior and Danvers trust that Hank would hand the files over? Is he obstructing the Annie K case? What does he have to gain from denying justice?

What does the spiral mean? 

In Season 1 of True Detective, spirals were a creepy recurring symbol tied to the Yellow King and his mystical murder spree. In Season 4, the first spiral appears when Danvers is sorting out Annie K evidence, arranging the files around her in a spiral. Is this purely an aesthetic throughline, or will this spiral serve as a bigger bind between Seasons 1 and 4? We'll be tracking that.

Who is Travis? 

Rose Aguineau (Fiona Shaw) is cleaning the catch of her hunt when, over a nearby radio, a man's voice squawks, "Is anybody there?" She turns to see a man standing nearby who's wearing nothing but a flannel shirt and long johns — he's not even wearing shoes. She calls him Travis and asks, "What do you want?" Silent but focused, he walks out into the icy landscape.

Dressed for the weather in a full parka, hat, gloves, and boots, and armed with a flashlight, Rose follows him. Eventually, he stops and does a dance, haunting and strange. He mimes screaming and rending his clothes. Then he points, and following his direction is how Rose finds the remains of the Tsalal scientists. 

When Navarro arrives on the scene, she's surprised when the old woman explains Travis led her here. "Travis is dead, Rose," the trooper says, to which Rose replies calmly, "I know." 

So, Travis may be a ghost. But who is he to Ennis? To Rose? And what does he know about the men in the snow? 

True DetectiveSeason 4 debuts on HBO and Max Jan. 14.