Journalists have been flocking to the planet Reah to discover how, despite its lack of resources and inhospitable climate, a massive top secret base had been established there. You are the last and most persistent of them, and the base's commander finally revealed that it was all part of a research mission surrounding a teleportation gateway. It connected with an alternate version of Reah in another dimension, one inhabited by strange humanoid beings, and full of bizarre technology and structures. Because this dimension somehow prohibited advanced human technology from working, a small outpost for the research team was set up on the other side, where they could observe the inhabitants first-hand. Now the commander has allowed you to see this version of Reah for yourself. Despite the return connection becoming increasingly unstable, your desire to be famous didn't let this deter you. With the return portal gone, now you simply must face the unknown.
Reah contains examples of:
- Abandoned Area: The research base set up by the team who first went through the portal before you.
- The City: The game features multiple cities, each of them rife with activity. In some places you can see inhabitants doing things in the background, some come out and talk to you, and you can even knock on the doors of various houses, even if most of them won't have an answer. A more modern city shows up visible through a fan duct near the end, strangely out of place.
- First-Person Ghost: The Journalist ponders this when looking into a mirror and unable to see his body."Why can't I see myself? I'm not a vampire, after all."
- Fish out of Water: Your character often reacts to his surroundings in a very confused manner, like a regular person would, and sometimes has conversations with people about this.
- Genre Savvy: At one point, your character refuses to cross a large body of water, saying "I'm not Indiana Jones."
- Glass-Shattering Sound: Used as a puzzle in the Desert City's temple, where four gongs must be struck in the right order to shatter a glass door.
- Going Native: How the scout team from the original version of Reah conducts their research. You even meet a few of them along the way.
- Hope Spot: Solving a puzzle in the desert's oasis brings up what the people said was the return portal, but it instead simply sends you to a jungle, still on the same world.
- Informing the Fourth Wall: The journalist tends to do this a lot.
- Only Smart People May Pass: After breaking into the Desert City's temple, the Alchemist forces you to solve a number of puzzles, just because he says so.Alchemist: I've prepared some more tests for you, and I expect you to put your thinking cap on.
- Ontological Mystery: For some reason, everyone claims to have seen you before, but you don't remember them.
- Our Ghosts Are Different: The first person you'll likely meet is a hooded phantom who used to be an alchemist, capable of appearing at will. Later in the game, after you leave the desert, he follows you through the rest of the game as a Spirit Advisor.
- Light and Mirrors Puzzle: Where you have to use sunlight bounced off a number of mirrors and through a lens to light the wood under a vat of dye.
- Note to Self: A valuable clue that unlocks the final area of the game is attached to a partial recording of the main character's own voice. He reacts to this with speculation that he's suffering from amnesia.
- Npc Roadblock: A phantom guard won't let you leave the Desert City without a source of water, due to the drought that increased after you entered.
- Philosopher's Stone: You can win one by beating the Alchemist four times in a row at a game of stones. It's useful for turning a lead weight to gold, as a flask of water you need is worth its weight in that metal.
- Product Placement: During the intro, Pepsi logos can be clearly seen on computer monitors in the outpost.
- Recycled Premise: The Reveal at the end would come around to be just as ambiguous as that of Sentinel: Descendants In Time, ironically Detalion's last game... until they announce Schizm III in 2019.
- Songs in the Key of Lock: One of the first puzzles of the game, to understand Reah's native tongue, is solved by synchronizing three talking faces on a fountain with various sounds in their vicinity.
- Speaking Simlish: The native language of Reah apparently sounds like English, only jumbled and randomly edited.
- Stock Video Game Puzzle: The final 3 puzzles in the game, each of which must be beaten three times. Fail, and the puzzle resets.
- One is a memory game with various symbols, where each new round has twice as many symbols to remember, and runs faster than the previous round.
- Another uses an inverted form of Towers of Hanoi, and each round has more pieces to stack.
- Sudden Downer Ending: The Alchemist appears one last time at the end of the game, glowing red instead of his usual blue; and explains that he is some kind of AI, that it was he that "dreamed" of everything you saw, and you are some sort of test subject being put through it. The reason people know you is because this wasn't the first time, and the only reason you don't know them is because the Alchemist wipes your memory at each restart. He caps it off by saying that he'll keep repeating this experiment as many times as he sees fit, then you're slapped with a big, fat "GAME OVER". There is no Happy Ending, if you were wondering.
- Title Drop: At the end of the opening narration: "Having no other choice, he simply had to face the unknown."
- Voiceover Letter: The last page of a couple of Reahan books is read by the Alchemist for you, which helps, considering your character can't read their language.
