The Watcher was the main antagonist of season two of the series, as well as the first other voiced character in the series besides Keisha/The Narrator. Not much is known about the Watcher before her appearance in the series, except that at one point she was a normal human being. When she meets Keisha in person, she tells her a story about when she was a little kid and was afraid of uncovered windows at night, even sometimes during the day. She was afraid of some unknown entity looking in the windows during the day and night, waiting to try and get her, and therefore she tried to keep the windows covered. It is not known what happened to turn her into what we experience in the series, but it could have something to do with the 'things' she was afraid of outside the windows.
First appearing in the bonus episode "Haugen, Montana” in between seasons one and two, it is implied that she has been tracking and following Keisha for a long time before she eventually 'meets' Keisha in season two, episode one "The Last Free Place".
In "The Last Free Place", The Watcher pulls Keisha over just outside Slab City in the deserts of Southern California, posing as a police officer. She stays in the police cruiser for several minutes before getting out and going to talk to Keisha. She asks Keisha if she knew how fast she had been going, and when Keisha rebuts "I don't know, how fast was I going?" the Watcher says she doesn't know either, that's why she was asking. She simply likes chasing things because they go fast. After talking for a couple more minutes, Keisha senses something is wrong, and asks to see some identification, to which the Watcher supplies in the form of a fake police badge. When she tries to leave, realizing the Watcher is someone bad and there to hurt her, the Watcher tells her that leaving hastily was a mistake and that she 'just wanted to talk'. She threatens Keisha, making it clear that she too knows about the weird, dangerous things in the dark, and she is one of them. She tells Keisha to be careful, and watch her back because she is being watched, before letting Keisha go.
The Watcher re-appears in episode six, "Badwater", following Keisha, once again, in the deserts of California, specifically Death Valley. After experiencing a sudden storm, she and Keisha end up in a small community in Death Valley that is home to the Amargosa Opera House and Hotel, where a once famous ballerina settled down to perform ballets to empty audiences. While still in her car tracking Keisha, before the town, the Watcher comes across a coyote in the road and has a moment with the coyote where she says that the coyote understands her better than any of the humans in the country. The Watcher decides to switch cars, and kills a couple that had come to the community on a trip, then steals there car, once again on the road. She decides not to kill Keisha just yet, and lets her go, continuing their somewhat one-sided game of cat-and-mouse.
In "Absent Family" she tracks Keisha to the abandoned farm house in Georgia where there was once an entrance to a Bay and Creek facility. She calls out to Keisha from the hood of another police cruiser she has stolen, with the police officer she stole it from dead inside. She admits that asking if Keisha is inside the house is a dumb question since she'd tracked her there, before coming into the house to grab her. Keisha tries to hide in the house but is eventually found by the Watcher after she breaks a window to escape. The Watcher grabs one of her arms, tight, and is about to drag her off when Keisha takes a piece of glass and stabs her in the chest. The Watcher barely reacts, but loosens her grip enough for Keisha to escape. Once outside, Keisha takes the police cruiser, and escapes, even though the Watcher was able to gain on her for a bit while running.
The Watcher catches up with Keisha in the next episode, "Prey". She follows her in a small car, and at first Keisha doesn't know it is her, despite the car following her for nearly two hours. Keisha later sees the car crashed in a ditch and becomes unsettled. Keisha starts to see a blue truck, with signs saying "I NOT BAD BOY" in the windows, more signs every time she sees the truck. Finally, while leaving a Cracker Barrel restaurant, Keisha sees the truck, now completely plastered with the signs, and The Watcher standing on the hood. Upon seeing her the Watcher starts howling an inhuman howl, dripping blood and scaring Keisha back into the cab of her truck where she drives off. When Keisha later pulls over to record one last message for Alice before she leaves the country, the Watcher finds her and finally captures her, telling Keisha they were 'going somewhere quiet where they could talk'.
In the season two finale "Why Am I Alive?" the Watcher has taken Keisha to an unknown location inside what sounds like an interrogation room. The Watcher talks to Keisha, wanting to know how much of this whole situation Keisha understands, and seemingly wanting Keisha to understand why it was she was sent to kill her. The Watcher, in an effort to make Keisha understand how futile her situation was, opens the door to the room to show her that they are , in fact, in a Bay and Creek facility, which means that both Bay and Creek and Thistle wanted her dead. As the conversation continues, the Watcher becomes more and more excited as Keisha understands what is actually going on, including the fact that it was possible Alice knew the entire time that this would happen to her. As the Watcher is about to kill Keisha, there is a knock at the door, and when she tells the person to wait, the knocking turns to banging. Finally, the door bangs open, Alice enters the room, a shot is heard, and it is assumed that she shoots and kills the Watcher to save Keisha.
In the series finale "An Ending", it is revealed that the Watcher is alive. She notes that she probably did die, but she is alive once more, all of it being a part of her "cycles". She says Alice and Keisha never saw her again in their lives, and, as their deaths at old age were permanent, never would again. The Watcher also mentions going to a diner and speaking to a man with a lot of rage, feeding into his ideas and giving him more. She doesn't have a name, but said if she had to pick one it would be "Thistle". She ends her segment by saying "Alice, the first thing I'd have to say is..." then she laughs and says "Shit...", mimicking Keisha's words in the second season's first episode.
- Voiced by actress/writer Roberta Colindrez.
- Described by Keisha as 'smart', and while the Thistle Men were dangerous in their mindless hunger, this person was more dangerous due to her calculating, well thought out moves. The fact that she wants to inflict pain and fear, to scare Keisha and cause her pain, rather than just mindlessly kill her like the Thistle Men is another thing that scares Keisha quite a bit.
- Like the Thistle Men, she gets something within her fulfilled when killing, and is addicted to it.
- There are others out there like her, as she says in one episode that the world will always 'need people like me' due to their unrelenting blood lust and willingness to kill.
- While she gets some sort of pleasure through killing, she also likes the feeling of pain for herself, as she wishes for the lightening during a sudden storm in the episode "Badwater" to strike her, so she could feel the electricity going through her body.
- How much pain she can actually feel is questionable, as she doesn't seem to respond much when Keisha stabs her with a glass shard from a window in "Absent Family". It could be that she doesn't feel much of anything due to her condition, and that is why she longs for the pain to begin with.
- It is implied that she is immortal and cannot die, or rather she can die but comes back at some point.
- It is also implied that she is the one who creates the Thistle men by finding already angery filled people and manipulating them. Though, she makes it clear that becoming such things is their choice.