More often than not, I like it when Game of Thrones changes on its way from the page to the screen. George R.R. Martin's books are immersive and sprawling, and the TV series is admirably tighter and more narrative-driven. Both are totally successful in their distinct own ways.

Several of my favorite scenes are totally original to the HBO series: Robert and Cersei's sad detente about the state of their marriage, Catelyn's dark confession to Robb's wife Talisa, or the tense mini-arc in which Arya served as cupbearer to Tywin Lannister. There have been some minor missteps along the way — but on the whole, the writers have done a stellar job streamlining and amending Martin's story to fit the needs of a TV series.

Until now. Sunday night's "Breaker of Chains" makes an alteration so wrongheaded and baffling that it single-handedly threatens to derail the arcs of both Jaime and Cersei Lannister.

Let's review. In the terrible scene — which takes place in the Great Sept of Baelor, after Jaime sends everyone else away — Cersei tears up as they stand together over Joffrey's body. "He was our son. Our baby boy." They kiss, but Cersei pulls away. Jaime becomes enraged. "You're a hateful woman. Why have the gods made me love a hateful woman?" he says, before pushing her to the ground and beginning to rape her. "Jaime, not here. Please. Stop it. Stop it. Stop it," Cersei says. Jaime says no. "Stop it. It's not right. It's not right. It's not right," Cersei says. Jaime says, "I don't care." The scene ends, disturbingly, as Cersei unsuccessfully begs Jaime to stop one last time.

I generally try to avoid making direct comparisons between the books and the TV series — but in this case, I think it's instructive to see how this scene was originally conceived. This is what George R.R. Martin wrote:

There was no tenderness in the kiss he returned to her, only hunger. Her mouth opened for his tongue. "No," she said weakly when his lips moved down her neck, "not here. The septons..."

"The Others can take the septons." He kissed her again, kissed her silent, kissed her until she moaned. Then he knocked the candles aside and lifted her up onto the Mother's altar, pushing up her skirts and the silken shift beneath. She pounded on his chest with feeble fists, murmuring about the risk, the danger, about their father, about the septons, about the wrath of gods. He never heard her. He undid his breeches and climbed up and pushed her bare white legs apart. One hand slid up her thigh and underneath her small clothes. When he tore them away, he saw that her moon's blood was on her, but it made no difference.

"Hurry," she was whispering now, "quickly, quickly, now, do it now, do me now. Jaime Jaime Jaime." Her hands helped guide him. "Yes," Cersei said as he thrust, "my brother, sweet brother, yes, like that, yes, I have you, you're home now, you're home now, you're home." She kissed his ear and stroked his shortly bristly hair. Jaime lost himself in her flesh. He could feel Cersei's heart beating in time with his own, and the wetness of blood and see where they were joined.

Turning this into a rape scene is not a meaningless alteration; it significantly changes the arcs of both Jaime and Cersei, and not for the better.

Let's start with Jaime, who has spent much of Game of Thrones as a prisoner. Jaime's arc is one of the trickiest and most rewarding in the series. The very first episode ends with him pushing a 10-year-old boy out of a window. At the time, it was hard to imagine anything that could make him sympathetic — and his subsequent scenes, which included a nasty brawl with Ned Stark and a proclivity for mocking his grieving widow Catelyn, didn't exactly move him toward the light.

But Jaime's unlikely path to redemption, which took up the entirety of the third season, literally began with his distaste for sexual violence. "When we make camp tonight, you'll be raped," he told Brienne after they were captured by Roose Bolton's men. "More than once. None of these fellows have ever been with a noblewoman. You'd be wise not to resist. If you fight them, they will kill you. Do you understand? I'm the prisoner of value, not you. Let them have what they want. What does it matter?" When Brienne challenged his advice, asking what he'd do if he was a woman, Jaime conceded the point: "I'd make them kill me. But I'm not, thank the gods." Despite his apparent callousness, Brienne's words clearly sunk in; later that night, Jaime devised a clever lie that saved Brienne from being raped.

The best scene of season three came when Jaime and Brienne shared a candid conversation in a bathtub. (Though she was initially embarrassed and frightened when he joined her, Jaime waved away her concerns: "Don't worry. I'm not interested.") There, Jaime revealed that his most notorious act — stabbing then-king Aerys Targaryen in the back — was secretly one of the most heroic acts in the entire series. Unbeknownst to the rest of the world, Aerys had made plans to burn all of King's Landing down along with him, and Jaime sacrificed his own honor and reputation to save the lives of millions, knowing he'd be branded as a villain and a traitor for life. In short, Jaime's defining trait suddenly shifted from arrogance to selflessness. It's a brilliant arc, and an arc that successfully positioned Jaime as the unlikely hero of the series — a man whose flexible moral code was actually far more noble than the upright Ned Stark. Brienne developed a new appreciation for his heroism, and Jaime came to appreciate Brienne's refusal to be victimized for her gender.

All of that careful character work was undone when Jaime raped Cersei on the floor of the Great Sept of Baelor. Jaime's act of sexual violence is totally out of character and shocking in its cruelty; less than a minute after Cersei expresses grief for the child they had together, he curses her and assaults her within feet of Joffrey's dead body.

We already know that Cersei was a victim of marital rape, and that she is once again being coerced into a second loveless (and presumably sexless) marriage with Loras Tyrell. But the relatively low status of even a highborn woman in Westeros hasn't kept her down; a woman, Cersei's main weapon is sex, and she's not shy about using it to get what she wants.

The chapter in A Storm of Swords is told from Jaime's perspective, so we can only guess what's going on in her head — but at the very least, the sex is clearly consensual. And while the act itself retains both its danger and its grotesqueness — having sex in a church next to your dead son's corpse will do that — Cersei is the one with power. There are two ways to read it: either she chose to have sex with Jaime for pleasure, or she chose to have sex with Jaime so he would be easier for her to manipulate.

Making the sex scene a non-consensual one removes all Cersei's power — and if there's one thing Game of Thrones doesn't need, it's another powerless woman. The series' sexual politics have been criticized before — and in my judgment, generally unfairly. Daenerys' early victimization was the first step toward a larger arc about her becoming a just, powerful ruler. Ros, a prostitute who was basically treated as a naked extra in Game of Thrones' premiere, became a valuable entry point to a story about women without power in Westeros. Osha, a captor and servant of the Stark family, used Theon's lust and underestimation of her gender to help Bran and Rick escape.

But I can't think of any comparable defense for the rape scene in "Breaker of Chains," which feels like a naked and ill-conceived attempt to push Game of Thrones into even darker territory. With those worries in mind, it's hard not to notice that this is the second consecutive episode in which a sympathetic male character has ordered a woman to leave his side without giving her a choice in the matter — and in both cases, the series has invited us to pity the man for the difficult decision he made.

Game of Thrones is set in a world that's uncommonly cruel to women, and I generally sympathize with the show's writers, whose depictions of misogyny and sexual violence have been unfairly treated as an endorsement. For the first time, I'm concerned that Game of Thrones has made a mistake it can't take back — and one that sets a troubling precedent for the show's future.

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