Given that Servant, the Apple TV+ show about a family reeling from the aftereffects of tragedy and their megalomaniac nanny who may or may not have supernatural powers, was an M. Night Shyamalan project, fans knew to expect a twist.

(Warning: Spoilers ahead for the series finale of Servant.)

The central mystery of the show—whether or not caregiver Leanne, played by Nell Tiger Free, actually had the power to turn a doll into a living baby, and whether those powers were angelic or demonic—teetered back and forth with every episode, some moments seeming to confirm one interpretation, others invoking the opposite. After keeping us guessing for four full seasons, Servant revealed in the final moments of the final episode what it was all really about.

As Season 4 drew closer to its conclusion, the audience was presented with two alternatives. One, as the Turner/Pearce family stubbornly believed, was that Leanne was simply an escaped member of a cult that called itself the Church of the Lesser Saints. Dorothy (Lauren Ambrose) discovers, by going through old tapes of her news broadcasts from a decade ago, that Leanne apparently became obsessed with her when she was a child in the clutches of the cult, and eventually escaped once she found a way into the Turner household, using a system of underground tunnels to spirit a stolen baby into their house and use their grief as leverage to pass it off as their own.

Apple TV+

This theory is seemingly confirmed by Leanne’s nemesis Uncle George (Boris McGiver), who comes clean to Dorothy’s husband Sean (Toby Kebbell) and her brother Julian (Rupert Grint) in episode 7, claiming all the religious smoke and mirrors was a ruse to get the Turners to return Leanne to the cult.

The second (and much more fun) possibility is that the Turners have been targeted by a wayward supernatural force, perhaps even a guardian angel of the Biblical sort, who has strayed too far from the light and is now using her powers for evil instead of good, with the fate of the world hanging in the balance. The cultish Church, seeming at first to be devil worshipers, might actually be a group of angelic beings hunting for Leanne only because they know what will happen if she turns to the dark side. Uncle George confirms this at the end of episode 7, when he begs forgiveness for lying to the Turners about what they have invited into their home.

And yet, still, for the next couple of episodes, the show continued to waffle back and forth. Is the Turners’ “fallen angel” theory correct? Or is Uncle George just nutty? Does Leanne actually have strange powers or is she just an expert at using coincidence to her advantage? If she isn’t a superhuman being, does she know? Or does she really believe that she’s something special?

Throughout the season, it appears that Leanne is embracing some form of power, repeatedly haranguing and mocking a skyward presence while animals attack or avoid her, admonishing the Turners to “be very careful” if they ever do something to annoy her. But the show’s savvy use of incidents that could be explained away if you wanted to keep everyone guessing until the very last minute. Is the ever-expanding sinkhole underneath their apartment building Leanne’s doing, or the product of strange weather combined with a weak foundation? Did Sean stab himself with a knife in episode 8 accidentally, or did Leanne control the blast of wind that threw him across the kitchen?

In the penultimate episode 9, titled “Awake,” Dorothy finally remembers and accepts, through her grief and her guilt, the terrible accident that brought the family to this crisis point, which she has spent that past four seasons completely blocking from her memory. Sean and Julian painfully remind her of her real baby’s death, explaining that Leanne has simply been taking advantage of the family this entire time.

In the following episode, “Fallen,” Dorothy and Leanne confront each other on the roof of the building in the middle of a nearly Biblical storm. Dorothy tells Leanne that she believes that she brought her son Jericho back to life, telling her, “It was the kindest thing anyone has ever done for me.” Yet, depending on how you see it, it’s impossible to tell whether she genuinely believes what she’s saying, or is just trying to get Leanne not to jump off the roof.

Apple TV+

Leanne, however, is too far gone, blaming herself for the Turners’ misery and for the fire that burned down her house when she was a little girl, killing her family. When lightning strikes the roof, she believes divine wrath has come for her at last, and when the Turners get into their car to wait out the storm, Leanne sets the apartment on fire, roasting herself alive within it in order to protect them.

In the aftermath, her body is never found, having fallen through the sinkhole and apparently disappeared. After Dorothy and Sean reconcile, Julian is approached by Officer Stephanie Reyes (Victoria Cartagena), who cryptically reminds him of the time his heart stopped on Christmas at the end of Season 2, and how Leanne revived him, implying that he was brought back to life to serve a higher purpose.

“We’re family now,” she says, while the remaining members of the Church of the Lesser Saints stand in the street behind her, staring spookily at Julian. As she walks away, Julian catches his reflection in the window of a coffee shop, the wings of a bird mural on the other side of the street spreading from his shoulders. When he connects the dots, he says, appropriately, “Holy shit.” Maybe he’s just seeing things. Maybe seeing is believing.

This is a preview of our pop culture newsletter The Daily Beast’s Obsessed, written by editor Kevin Fallon. To receive the full newsletter in your inbox each week, sign up for it here.