Remember what I said in my recent review of Nineteen Eighty-Four?
Most of the analyses I read online consider the climax of the book to be where Winston Smith and Julia betray each other. It seems clear to me, however, that the true climax occurs much earlier in the book, when they believe they are joining the Brotherhood, an organization dedicated to opposing the ruling Party.
"In general terms, what are you prepared to do?"
"Anything that we are capable of," said Winston.
O'Brien had turned himself a little in his chair so that he was facing Winston. He almost ignored Julia, seeming to take it for granted that Winston could speak for her. For a moment the lids flitted down over his eyes. He began asking his questions in a low, expressionless voice, as though this were a routine, a sort of catechism, most of whose answers were known to him already.
"You are prepared to commit murder?"
"To commit acts of sabotage which may cause the death of hundreds of innocent people?"
"To betray your country to foreign powers?"
"You are prepared to cheat, to forge, to blackmail, to corrupt the minds of children, to distribute habit-forming drugs, to encourage prostitution, to disseminate venereal diseases—to do anything which is likely to cause demoralization and weaken the power of the Party?"
"If, for example, it would somehow serve our interests to throw sulphuric acid in a child's face—are you prepared to do that?"
At that point any hope for the future is lost, those opposing evil having shown themselves to be no better than their opponents. Everything after that is dénouement.