It is set in 1979, when a CIA cryptoanalyst Adam leaves the city of Boston and moves to the countryside estate of Blackstone with his wife, Emma, believing he needs peace and quiet in order to focus on breaking the code that may alter the course of the Cold War.
However, Adam soon finds a mysterious diary in the attic. It was written by Nicolas Hyde, whose lineage had traditionally owned Blackstone and who lived there during the 19th century. Once opened, the diary carries the nightmares of the past right into Adam's times, putting the lives of Adam and Emma in great danger. The game is then split between Adam's and Nicholas' chapters.
The Tropes Inside:
- Accentuate the Negative: Adam, who manages to find a new thing to complain about with pretty much every new sentence he utters. Sometimes, he even manages to complain about the things he himself did and wanted, as Emma will immediately point out.
- Ambiguous Situation: Was Adam going insane, or were there really stalkers, and was Emma really a spy for the Soviets?
- An Axe to Grind: In the opening a (yet-unnamed) killer picks up an axe from the wall and uses it to kill Emma, whom he already had tied to a chair. This is all portrayed from the killer's unbroken first-person perspective as well.
- The Cynic: Adam almost never runs out of things to complain about. Then again, it could be justified, given the high stakes of his job.
- Evil Sounds Deep: The voice of the killer in the opening scene is deep and also quiet, which only adds to the menace.
- First-Person Ghost: In spite of the game's frequently photorealistic locales, this trope is still played straight, as Adam and other characters only have visible arms during the first-person cutscenes, and legs & lower body are equally invisible.
- Idiosyncratic Difficulty Levels: Here, they are named Adventure, Standard, and Beast.
- In Medias Res: The opening is portrayed from the unknown killer's perspective, who has already killed Adam and has Emma tied to a chair, before killing her with an axe after a short conversation. The game then flashes back to "one week earlier".
- Jump Scare: These become frequent during the game's second half.
- P.O.V. Cam: While some cutscenes still use overhead bird's eye views, the majority are done directly in first person. This includes the opening scene, portrayed entirely from the perspective of the killer.
- Meaningful Name: Nicolas Hyde has a Jekyll & Hyde style evil alternate personality.
- Maybe Magic, Maybe Mundane: It's left ambiguous as to whether Adam was somehow possessed by the ghost of Nicolas' evil alternate personality, or whether he somehow spontaneously manifested a hereditary case of disassociative identity disorder after reading Nicolas' diary, despite no apparent past history of such. It's also ambiguous as to whether Nicolas is really encountering the ghosts of his evil alternate personality's victims, or whether he's merely hallucinating the entire thing due to subconscious memories of the crimes.
- Multiple Endings: Four of them, largely determined by two Last Second Ending Choices.
- Opposites Attract: We see the difference between Adam and Emma's personalities from their first cutscene together, as he is complaining during the entire drive to Blackstone, while Emma keeps looking at the bright side of life.
- Resources Management Gameplay: While Adam's sections are purely exploration and puzzle-solving, in Nicolas' sections you need to collect and manage a supply of matchbooks and kerosene for lighting candles and fueling your lamp, rather similar to Amnesia: The Dark Descent. Later in the game you obtain a gun and have to manage the rare supply of bullets.
- Serial Killer: Nicolas soon realizes he's on the trail of one. It turns out to be the work of his evil alternate personality. Adam, meanwhile, is menaced by... something, though it's initially unclear whether it's Soviet spies or just some psycho. It all turns out to be the work of Adam's own evil alternate personality as well.
- Serious Business: Adam is convinced his work is all that stands in the way of the nuclear annihilation.If I don't break the code, this country will be like a basket full of nuclear mushrooms.
- Shell-Shocked Veteran: The killer in the opening scene justifies his murders entirely with military metaphors, saying "War demands casualties!" in response to Emma screaming why he killed her husband, and then replying with "I'm setting the frontline." to another one of her fruitless questions.
- Unexpected Gameplay Change: For the most part, the game is a first person adventure game focused on environmental exploration and puzzle solving. Then, in Nicolas' sections, you find a gun, run into one of the cursed souls, and suddenly find yourself in a full-on video game Boss Battle.