In 1984 by George Orwell, Room 101 of the Ministry of Love is where evil itself resides. Big Brother monitors every citizen, so The Party knows every single person's greatest fears. Room 101 is the last resort for torture. The final phase of re-education. Nobody emerges from Room 101 without submitting to Big Brother, without betraying everyone they know in service of Big Brother.
Winston, the main character, undergoes every type of torture imaginable. Through beatings, sensory deprivation, forced starvation, and all kinds of psychological torture. And, still, he refused to talk. He'd remained unshakable for so long.
The thing that is in Room 101 is the worst thing in the world.
Winston is forced to watch other prisoners go into Room 101. Eventually, it's his turn. A member of The Party named O'Brien straps him to a chair.
“You asked me once," says O'Brien, “what was in Room 101. I told you that you knew the answer already. Everyone knows it. The thing that is in Room 101 is the worst thing in the world. It varies from individual to individual. It may be burial alive, or death by fire, or by drowning, or by impalement, or fifty other deaths. There are cases where it is some quite trivial thing, not even fatal."
The door opens again. A guard comes in, carrying something made of wire, a box or basket of some kind. He sets it down on the further table. Because of the position in which O'Brien is standing. Winston cannot not see what the thing is.
“In your case," says O'Brien, "the worst thing in the world happens to be rats."
One of the other methods of torture involves negative feedback—what Leftists would call “gaslighting." It means convincing someone that they're absolutely insane—that they no longer have a grasp on reality.
Life has become so much like 1984 that we can look at the torture scenes and actually somewhat relate.
At one point, O'Brien tells Winson, “We do not merely destroy our enemies, we change them." Compare that to this quote: “The philosophers have only interpreted the world, in various ways; the point is to change it." That's Karl Marx, describing the Marxist mission. And this requires every aspect of life to be determined by political activism.
This idea has not gone away. I'm sure you've noticed. It's practically the mission statement of the Left today.
A few years before his death, Orwell said, "Every line of serious work that I have written since 1936 has been written, directly or indirectly, against totalitarianism."
The entire dystopia of 1984 is based on The Soviet Union. Let's just say it's no coincidence that Big Brother has a mustache.