“Stupefy!” yelled Harry. He had edged right around to where the goblin stood beaming up at the now headless wizard and taken aim at her back as she peered around the fountain for him. She reacted so fast he barely had time to duck.

“Protego!”

The jet of red light, his own Stunning Spell, bounced back at him. Harry scrambled back behind the fountain, and one of the goblin’s ears went flying across the room.

- Harry Potter and the Order of the Phoenix, Chapter 36 (The Only One He Ever Feared)

And in this whole sequence, she is remarkably quick to process everything. The pieces click into place so fast for her nobody can can keep up.

“Gold!” laughed Bellatrix, still attempting to throw off her brother-in-law, her free hand groping in her pocket for her wand. “Take your gold, filthy scavenger, what do I want with gold? I seek only the honour of his — of—”

She stopped struggling, her dark eyes fixed upon something Harry could not see. Jubilant at her capitulation, Lucius threw her hand from him and ripped up his own sleeve —

“STOP!” shrieked Bellatrix. “Do not touch it, we shall all perish if the Dark Lord comes now!”

Lucius froze, his index finger hovering over his own Mark. Bellatrix strode out of Harry’s limited line of vision.

“What is that?” he heard her say.

“Sword,” grunted an out-of-sight Snatcher.

“Give it to me.”

“It’s not yorn, missus, it’s mine, I reckon I found it.”

There was a bang and a flash of red light: Harry knew that the Snatcher had been Stunned. There was a roar of anger from his fellows: Scabior drew his wand.

She is not attacking mindlessly at all. She isn't bothering to talk to them because she knows it's of no use and they're only going to waste her time. She stuns one of them before Scabior even thinks of drawing his wand! She is one woman and she stuns four of them before they even think of defending themselves!

“What d’you think you’re playing at, woman?”

“Stupefy!” she screamed. “Stupefy!”

They were no match for her, even though there were four of them against one of her: She was a witch, as Harry knew, with prodigious skill and no conscience. They fell where they stood, all except Greyback, who had been forced into a kneeling position, his arms outstretched. Out of the corners of his eyes Harry saw Bellatrix bearing down upon the werewolf, the sword of Gryffindor gripped tightly in her hand, her face waxen.

She forces Greyback to kneel instead of stunning him because she knows she needs him conscious to answer her questions. In the middle of taking out four men simultaneously, she's already sorting them into categories, just as she does with the trio later. That kind of thinking mid-combat is extraordinary.

i think Harry slightly misreads her here, or rather, he reads her from the outside without understanding her internal logic, which makes sense for someone like Harry whose mind doesn't work anywhere near as fast. She's acting without hesitation, which is a completely different thing from conscience. Conscience is irrelevant here because these men are obstructing something critical and they will not respond to reason and she has no time. What Harry is reading as absence of conscience is truly the absence of needing to justify or explain her actions to people who are unable to understand them.

I also think a minority of people make the mistake of reading this as 'calculating', but that's not what's happening here. Her cognition is too fast and quick for even her own body to catch up to, which is why she seems so out-of-control. She is frenzied and wild here, but that does not mean out of touch with reality or crazy in that sense at all.

In brains like hers, pattern recognition becomes so fast and so refined that it bypasses calculation entirely. The conclusions arrive before one can think them through, and this is also different from what people call 'intuition', which is based entirely on internal feelings rather than connecting dots observed through the senses in the way Bellatrix is doing. That gap between where the mind already is and where the body still is often reads as frenzy.

The following sequence proves her point that these are irrational people not worth attempting to reason with. Just look at how Greyback is responding:

“Where did you get this sword?” she whispered to Greyback as she pulled his wand out of his unresisting grip.

“How dare you?” he snarled, his mouth the only thing that could move as he was forced to gaze up at her. He bared his pointed teeth. “Release me, woman!”

“Where did you find this sword?” she repeated, brandishing it in his face. “Snape sent it to my vault in Gringotts!”

“It was in their tent,” rasped Greyback. “Release me, I say!”

She waved her wand, and the werewolf sprang to his feet, but appeared too wary to approach her. He prowled behind an armchair, his filthy curved nails clutching its back.

Sadly, minds like hers are severely underestimated, especially in women, hence the fandom's branding of her as crazy. They are often reduced to feminine intuition and people tend to not take them seriously. The gendered insults are everywhere in this scene, with Scabior calling Bellatrix 'missus' and Greyback and other Snatchers constantly addressing her as 'woman' to demean her.

Her fury at the sloth of Narcissa's mind is so relatable that I can feel it in my bones.

“Draco, move this scum outside,” said Bellatrix, indicating the unconscious men. “If you haven’t got the guts to finish them, then leave them in the courtyard for me.”

“Don’t you dare speak to Draco like —” said Narcissa furiously, but Bellatrix screamed,

“Be quiet! The situation is graver than you can possibly imagine, Cissy! We have a very serious problem!”

She stood, panting slightly, looking down at the sword, examining its hilt. Then she turned to look at the silent prisoners.

“If it is indeed Potter, he must not be harmed,” she muttered, more to herself than to the others. “The Dark Lord wishes to dispose of Potter himself. … But if he finds out… I must… I must know. …”

She turned back to her sister again.

“The prisoners must be placed in the cellar, while I think what to do!”

“This is my house, Bella, you don’t give orders in my —”

“Do it! You have no idea of the danger we are in!” shrieked Bellatrix. She looked frightening, mad; a thin stream of fire issued from her wand and burned a hole in the carpet.

Narcissa hesitated for a moment, then addressed the werewolf.

“Take these prisoners down to the cellar, Greyback.”

“Wait,” said Bellatrix sharply. “All except… except for the Mudblood.”

- Harry Potter and the Deathly Hallows, Chapter 23 (Malfoy Manor)

Even Narcissa does not take her seriously here. Bellatrix has to tell Narcissa to tell Greyback what to do, and it's Narcissa's cold and controlled order he listens to, after defying Bellatrix and baring his teeth at her.

It hurts me so much how much Bellatrix is dismissed. She has just, in mere minutes, stunned four men, held Greyback on his knees, and correctly identified a problem that could get everyone in that room killed and nobody else could see it. She is objectively the most intelligent and powerful person present by far, and she has to ask Narcissa, of all people, to pass on her order to a man she just had on the floor, only because Narcissa does not have Bellatrix's emotional and cognitive depth and that flatness is unfortunately taken more seriously by general society! It's beyond disheartening how unfair it is.

Even Voldemort, who respects her talent so much and made her the only senior female Death Eater and trained her in the Darks Arts personally, does not listen to her about Snape, despite her excellent reasoning, despite personally telling her Snape tried to prevent him from taking the Philosopher's Stone, and perhaps later coming to the same conclusion himself when the wand wasn't working for him.

At the same time, her body is very languid and she likes to take in every moment fully.

Snape gestured Narcissa to the sofa. She threw off her cloak, cast it aside, and sat down, staring at her white and trembling hands clasped in her lap. Bellatrix lowered her hood more slowly.

- Harry Potter and the Half Blood Prince, Chapter 2 (Spinner's End)

The contrast with Narcissa, who, due to her constant restlessness, moves around very fast but her mind is slow, is notable. What does it mean to lower a hood slowly while your sister is trembling? It means you're in absolutely no hurry and the act of uncovering your own face is something you intend to savour. The slow reveal is honestly almost erotic, that management of your own unveiling, as though the world can wait while you enter it on your own terms...

Bellatrix Lestrange walked slowly around the prisoners, and stopped on Harry’s right, staring at Hermione through her heavily lidded eyes.

- Harry Potter and the Deathly Hallows, Chapter 23 (Malfoy Manor)

What a gorgeous, sensual image. The langudity of the circling and the heavily lidded eyes are the same quality expressed through two different parts of the body simultaneously. She is luxuriating. The prisoners are almost incidental and what she is really doing is tasting the moment.

Also:

“Potter?” shrieked Bellatrix, and she backed away, the better to take in Harry. “Are you sure? Well then, the Dark Lord must be informed at once!”

- Harry Potter and the Deathly Hallows, Chapter 23 (Malfoy Manor)

This one is perhaps the purest expression of it. She wants more of him in her field of vision. It is a voluptuous impulse, the way she steps back to make more room for the pleasure of seeing. She arranges herself so she can receive more...

That languid, sensual physicality and lightning-fast brain reflexes give her an extremely unique combination of brilliance and sensuality. In neuroscience, cognitive processing speed is defined as distinct from sensory absorption rate. Some brains, particularly highly brilliant ones that are wired for pattern recognition (hence Bella being the only one to figure out Snape's true loyalty), process information extraordinarily fast, and those same brains are often deeply, almost greedily sensual. They want to drink in the physical world slowly. Bellatrix has that brilliant quickness of mind and the voluptuous languor of body and the tension these qualities exist in is delicious to read.

She canonically has one of the most high-bandwidth mind of any character, and I would say it's faster even than Dumbledore's because unlike him, she gathers every last detail before coming to her conclusions while Dumbledore often misses some details (like Voldemort clearly wanting the DADA job), though that could also be explained by his emotions or philosophies overriding reason. She is highly attuned to reality, more so than even Voldemort and Dumbledore, even though she also feels very, very deeply, and it's her the fandom calls crazy... So tragic.

They like to peek ☠️

I even remember reading a theory around 2011 that the reason Bellatrix was absent from most of HBP was because she was pregnant with Voldemort’s child! (Wonder how the person who wrote it felt when Cursed Child came out…)

One of the most recurring falsehoods within the fandom has been perpetuated for so many years and so widely spread that it has almost become reality. People who claim to know the series intimately claim this lie as canon and angrily defend it, accusing those who disprove it of having a distorted view of the character. I've already discussed extensively why the idea that Merope Gaunt (Voldemort's mother) used Amortensia on Tom Riddle Snr is not canon but merely a theory. You can find the italian video HERE, I heve post the written version in English as well HERE.

But related to this theory, it follows today's topic. The idea that Voldemort was born physically incapable of love because of the way he was conceived not only flattens the character and the story but also clearly violates all the canonical information we have.