A brief twitch of panic was countered by the thought that Professor Quirrell had knocked her out to prevent her from hearing the Dark Lord's cringing servant suddenly turn into a hardened criminal and then an expert battlemage. Which was good, because she wouldn't have heard Harry's voice saying 'Expecto Patronum'.
Harry drew back the hood of the Cloak, pointed his wand at Bellatrix, and whispered as gently as he could, "Innervate."
From the way Bellatrix's body jerked a little, Harry didn't think he'd managed to get it quite gentle enough.
The sunken dark eyes opened.
"Bella dear," Harry said in his cold, high voice, "I am afraid we've run into a bit of a problem. Have you recovered enough to do small magics?"
There was a pause, and then Bellatrix's pale head nodded.
"Very good," Harry said dryly. "I won't ask you to walk unaided, Bella dear, but I am afraid you must walk." He pointed his wand at her. "Wingardium Leviosa."
Harry kept the flow of force down to something he could sustain for a while, and it was still probably lifting two-thirds of her current body weight. She was... thin.
Slowly, as though for the first time in years, Bellatrix Black pushed herself to her feet.
Amelia strode into the duty room, Auror Li and his silver badger following behind her. She'd spun her Time-Turner the moment she'd heard the alarm, and then spent a tense hour preparing her forces for entry. You couldn't loop time within Azkaban itself, Azkaban's future couldn't interact with its past, so she hadn't been able to arrive before the DMLE had gotten the message, but she should have arrived in time...
Her eyes went straight to the corpse, uncloaked and looking very dead, floating beyond the viewing window.
"Where is Bellatrix Black?" Amelia demanded, showing no fear before the creature of fear.
Even her own blood froze for an instant, as the corpse parted its lips, and gurgled, "Do not know."
Harry watched, now fully invisible once more, as Bellatrix slowly leaned down, took Professor Quirrell's wand (which Harry dared not touch), and slowly straightened again.
Then Bellatrix pointed the wand at the snake, and said, her voice precise though it was still a whisper, "Innervate."
The snake did not stir.
"Shall I try again, my Lord?" she whispered.
"No," Harry said. He swallowed the sick feeling. Harry had decided to say the hell with it and try to revive Professor Quirrell after he'd realized that the Dementors had probably alerted the Aurors by now. His high, cold voice went on, unperturbed, "Do you think you are able to perform a Memory Charm, dear Bella?"
Bellatrix paused, and then said, hesitantly, "I think so, my Lord."
"Eliminate that Auror's last half-hour of memory," Harry commanded. He'd thought a bit about whether he wanted to provide any justification for that, what he would say if Bellatrix asked why they weren't just killing him, in which case Harry would explain that they were pretending to be a different power group and then tell her to shut up -
But Bellatrix simply pointed her wand at the Auror, stood silently for a time, and finally whispered, "Obliviate."
She swayed, then, but did not fall.
"Very good, my dear Bella," Harry said, and chuckled thinly. "And I will ask you to carry that snake."
Again, the woman said nothing, demanded no explanations, didn't ask why Harry or the apparently-invisible Patronus caster couldn't do it. She only staggered to where the long snake lay, slowly bent over, picked it up, draped it over her shoulder.
(A tiny little part of Harry observed that it was very relaxing to have a minion that would just follow orders so unquestioningly, and even got as far as thinking that he could totally get used to having a minion like Bellatrix, before that mind-fraction was screamed into silence by his mortally offended remainder.)
"Follow," the boy commanded his minion, and began to walk.
It was starting to get crowded in the duty room, almost too crowded to breathe, though there was still space around Amelia herself; if needing to breathe meant that you had to crowd Director Bones, it was better not to breathe.
Amelia looked at where Ora was fiddling with Auror McCusker's mirror. "Specialist Weinbach," she barked, causing the young witch to start. "Any response from One-Hand's mirror?"
"None," Ora said nervously, "it's... I mean it has to be jammed, not dead, carefully jammed because it didn't set off the alarms, but the line is so blank the mirror might as well be broken..."
Amelia didn't let her expression change, though the part of her that was already mourning One-Hand got a little sadder and a lot more angry. Seven months, he'd had seven months left until his retirement after a full century of service. She remembered him as an eager young Auror, so very long ago, and his whole career he'd served the DMLE with perfect loyalty, at least when it came to anything really important...
Someone would burn for this.
The Dementor still hovered outside the window, casting its useless shadow of dread over their operations; all the creature could do was gurgle its lack of knowledge or fail to reply at all, when asked questions like 'Did Bellatrix Black escape?' and 'Why can't you find her?' and 'How is she being hidden?' Amelia was starting to worry that the criminals were already gone, when -
"We found a hole in the roof over C spiral!" someone shouted from the doorway. "Still open, ward circumventions still active!"
Amelia's lips peeled back in a smile like a wolf opening its jaws to eat.
Bellatrix Black was still in Azkaban.
And in Azkaban, Bellatrix Black would remain forever.
She took a stride toward the window, ignoring the Dementor now, and looked up at the sky above, to check with her own eyes the patrolling broomsticks. She couldn't see the whole sky from here, but she saw ten brooms go past on a patrol pattern and that already ought to be enough to catch anyone, though she fully meant to put every broom she could in the air. Her Aurors were equipped with the fastest racing broom currently on the market, the Nimbus 2000; no unsuccessful chases for her people.
Amelia turned back from the window, and frowned. The room was getting ridiculously crowded, and two thirds of these people didn't need to be here, they just wanted to be close to the center of the action. If there was one thing Amelia couldn't tolerate, it was people who did what they wanted instead of what was needed.
"All right, you lot!" Amelia bellowed at them. "Stop hanging around here and start securing the top level of each spiral! That's right," she said to the looks of surprise, "all three! They could tunnel through a floor or a ceiling to go between them, in case you hadn't worked that out! We're going down level by level until we catch them! I'll take C spiral, Scrimgeour, you're on B..." She paused, then, remembering that Mad-Eye had retired last year, who could she... "Shacklebolt, you're on the A spiral, take with the strongest other fighters! Check every set of cells you pass, look under blankets, do the full set of detection Charms in every corridor! Nobody leaves Azkaban until the criminals are caught, nobody! And..." People looked at Amelia in surprise as her voice trailed off.
The criminals had invented some way to prevent the Dementors from finding Bellatrix Black.
That ought to have been impossible.
It chilled her blood, contemplating that. It was like...
Amelia took a deep breath, and spoke once more, in a voice of steel command. "And when you catch them, make bloody sure they're the real criminals and not our own people forced to take Polyjuice. Anyone behaves oddly, check them for the Imperius Curse. Keep each other in sight at all times. Don't assume an Auror uniform is friendly if you don't recognize the face." She turned to the communications specialist. "Tell the broomsticks. If one of the brooms peels off for no reason, half of them are to hunt it down while the rest keep patrolling. And change the harmonics on everything changeable, they may have stolen our keys." Then back to the rest of the room. "No Auror is above suspicion unless they have no family left to threaten."