WARNING: The following contains spoilers for the third season of HBO's True Detective.

The third season of True Detective may be the biggest labyrinth the HBO anthology crime drama has laid down. Focusing on the disappearances of young Will Purcell and his sister Julie in 1980 Arkansas, the story has already fingered a plethora of suspects in two other time periods, 1990 and 2015, while hinting at a larger conspiracy spanning three decades.

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With evidence of Julie resurfacing in the '90s, and the case being reopened, we learn in the present the wasn't truly case solved; lead detectives Wayne Hays (Mahershala Ali) and Roland West (Stephen Dorff) never got it right. But, as it turns out, they may have also overlooked important details as to who could have killed Will: none other than Julie herself.

Everyone assumes the same people who kidnapped Julie also killed Will. In the season premiere, "The Great War and Modern Memory," Will's body was found in a cave in the woods, while Julie went missing. Such evidence as Will's bike, a swath of cult-like straw dolls, and testimonies from the kids who played in the area combined to point to one perpetrator for both crimes. However, additional clues have been dropped that suggest Julie may have killed her brother and then fled, either staying off the grid for good, or else being kidnapped.

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After Julie's fingerprints are found, along with possible security-camera footage of her as an adult in 1990, she allegedly calls the police hotline. "We left him resting," she says, at first sounds nonsensical, as Julie doesn't indicate who she's talking about. However, Will’s body was found, posed lying down with his hands clasped together as if in prayer. We want to believe a child isn't capable of such a horrendous act, but by the very nature of True Detective, Julie should be considered a suspect.

Another detail possibly linking Julie to Will's death comes from a line delivered by Amelia, Wayne's wife and one of the teachers who helped to investigate the case. She wrote a book about the siblings and, after extensive research, reveals Will's body appeared as if it were treated with "affection." Wayne tells her that kind of behavior isn't uncommon among people who kill children, but Amelia theorizes that Will's body was posed in that manner by someone who loved him. In other words, Julie.

The most damning clue, however, is the peephole in the Purcell home. The detectives noted it early on, but assumed it was the siblings' way to pass notes. We never find out who made it, but now it's suspected that Tom Purcell (Scoot McNairy) spied on his daughter. Of course, it could be that Will spied on his sister, and made her feel threatened, which could have led to her doing something drastic in the woods that fateful day.

Now, there's still the possibility Julie could have killed him, but with no malicious intent. Innocent play could have resulted in an accident; in her guilt, Julie may have tried to hide the evidence, and point fingers elsewhere. But on True Detective, Julie, like virtually everyone else, remains a suspect.

Airing Sundays at 9 p.m. ET/PT on HBO, True Detective stars Mahershala Ali, Mamie Gummer, Stephen Dorff, Scoot McNairy, Carmen Ejogo and Ray Fisher.