Hysterical laughter provided a macabre soundtrack as Doctor Strange collapsed to the floor.
Cavendish, his hands shaking so much that the smoking gun nearly skittered out from his fingers, stood over the body with the maniacal laughter booming in his ears.
"Shut up," he said quietly, more to himself than anyone else. Hearing this, Batman shook with mirth he couldn't control, retching hyena howls. "Shut up, shut up!" The psychiatrist broke into a shout, pressing one clenched fist to the side of his head.
Shrill laughter continued to pollute the air for a split second after the cry rang out, then it gradually died down to gasping whoops and then it was nothing but echoes bouncing back and forth on the cavernous walls, leaving Batman weak and nauseous.
"I refuse to be your pawn anymore, Strange." Cavendish told the felled doctor, who groaned and rolled over onto his side. He had managed to get away with nothing more lethal than a shot in the shoulder, although this left him steadily pooling thick red blood on the floor. Coughing weakly from the acrid after-smell of gunpowder, he clasped a hand over his injured shoulder to stem the bleeding and pressed his sweating face to the cool concrete.
"You've pushed me around for long enough. I never wanted to be a part of your ridiculous plans; all I've ever wanted to be is a good psychiatrist, someone who helps the inmates, not subjects them to crazy experiments. Well I've had enough, it ends here."
Joker would have applauded had his wrists not been strapped down.
"I am…" Doctor Strange gingerly pushed himself up, mindful of the weapon that was still trained on him. "I am sorry that you feel that way, Cavendish. If perhaps you had thought to tell me your feelings earlier, we could have avoided all this."
The taller man backed off warily as the other stood, swaying a little uncertainly on his feet and clutching at his wound. Cavendish came up short and glanced wildly over his shoulder when he realised that he had backed straight into the machine.
'Ten bucks he doesn't have the guts to shoot again.'
'I wouldn't be so sure…' Batman thought back, even though he was irritated by the mental interruption and disgusted with the mirth he'd been forced to express. But it was true; Cavendish looked just about desperate enough to shoot again, this time to kill. The Dark Knight had seen that look so many times before and he knew how it would end if he couldn't get free in time to stop it.
With this thought burning in his mind, he fought to free himself so that in turn he could free the two psychiatrists from the death struggle they were locked in, but it was no good. Obviously, Doctor Strange had foreseen reluctance in his patients, for the straps were too heavy duty for even the Batman's enhanced strength. Try as he might to break free, he knew in the more rational part of his brain that there was nothing he could do except watch this death dance played out. It wouldn't end until one of the psychiatrists were dead.
"Arkham is sick, sick!" Doctor Cavendish was screaming, his face twisted with passion, a thin line of saliva running from the side of his mouth. "Sicker than any of its inmates and you Hugo, you're the cancer that spreads the sickness! Stop this madness now, or I'll stop it myself!"
There was a deafening bang as the gun was fired again. Strange easily dodged the wild shot as it went sailing over his head to become embedded in the floor just shy of Joker's feet, sending up little shards of concrete and dust. Letting his momentum carry him forwards, Doctor Strange lunged at the shooter, grabbing him by the lapels of his neatly pressed jacket and slamming him bodily into the machine. A sickening crunch announced something inside of Cavendish breaking. The psychiatrist writhed in pain, dropping the gun to the floor with a clatter.
"You have been working too hard, Cavendish," Strange snarled up in the taller man's face, slamming him against the machine again. "I think perhaps you should take a vacation." Wrenching a wire free of the contraption, sending electrical sparks spitting and flying, he jammed the loose end up against Cavendish's neck.
A horrifying, anguished scream sounded as thousands of volts went coursing through the psychiatrist's body. Batman closed his eyes and turned his face away, not wanting to share in the man's last agonising moments, but he could still see it being played out vividly behind his closed eyelids, transmitted from the Joker who was watching it all avidly. Against his will, Batman saw the smoking body hit the floor, saw Doctor Strange stand calmly over it, pushing his spectacles back up his nose with one finger.
"What a pity…" the doctor murmured, delicately prodding the corpse with the toe of his shoe. "I shall have to act as the buffer myself now."
"You're not going to be doing anything, Strange; you've just killed a man," Batman growled, struggling ferociously to free himself once again. More than anything he wanted this insane killer brought to justice, even if handing him in would mean losing his own freedom. The Dark Knight, after all, was a wanted criminal.
"It is all for the progress of science," Strange murmured distractedly, as if he had done nothing more dramatic than tread on an insect in his path. He reached out to the machine, in his concentration forgetting about his gun shot wound, and was forced to wince and draw back. The once-white sleeve of his laboratory coat was now stained a bright, lurid red. He was losing a lot of blood, might only have minutes of consciousness left – he would have to complete the experiment swiftly.
'Another escape plan would be great right around now.' Joker's voice broke into Batman's thoughts as he watched the squat psychiatrist feverishly turning dials and flicking switches.
'I came up with the last one, it's your turn,' he replied irritably, frustratingly devoid of any ideas. His mind felt blank, exhausted.
Doctor Strange had finished adjusting the controls and now he attached four electrodes to his own forehead and temples, linking him with the two other men. Eyes shining with excitement and an oily sheen of sweat filming his face, he turned to his test subjects and announced "It is begun!" Letting out a wild shriek of laughter, he turned back and threw the final lever needed to set it all in motion.
There was a crackle of electricity and all the lights dimmed for an instant only to flare up even more brilliantly. Batman had time to hope that the experiment wasn't going to work, that maybe something vital had been broken when Cavendish was bashed against the machine, and then the pain hit him. It was excruciating, more painful than broken bones or fire or gun shot wounds, it filled his world and threatened to destroy him. There had never been pain like this before.
Gritting his teeth to keep from crying out, he hunched into himself as much as his bonds would allow and concentrated on embracing the pain and turning it to his advantage as he had been taught by Ra's Al Ghul. It was difficult, almost impossible, requiring a superhuman effort of will that surely was beyond his abused and battered body, but after a few moments he thought that he was beginning to master it. Instead of feeling as if his whole body was being consumed by indescribable pain, he found he was able to discern the exact location and nature of the hurt. Concentrating harder, shaking with the effort, he could feel electricity from the electrodes sizzling and burning around the inside of his skull. He found he could actually feel the essence of his mind being dragged out along the wires to Strange's brain, whilst the fundamental parts of Joker's mind was forced into his consciousness and made an integral part of it.
He lost control for a moment when the full force of the psychopath's mind hit him, making him cry out. Everything, including his sense of self, ceased to exist in that screaming, jumbled mess of sights and sounds and sensations. Things bled and ran into each other in unholy union, skittering and slipping, with no coherent pattern to aid understanding. Nothing stayed the same for long, changing and mutating even as he looked at it. Tyrants turned to victims and pleasure to pain and lovers to executioners. One moment he was a child with his face in the mud, next a man firing a gun, then something that was abstract and insubstantial, nothing but an idea of a concept. He thought he was going to throw up.
That feeling, so personal and primal, brought him out of Joker's nightmare world and back into his own pain. The pain was okay because he could control it and he knew now how he was going to use it. But he wouldn't be able to do it alone.
Ignoring Doctor Strange, who was swaying and gasping in his own world, he glanced across to Joker. The man was slumped awkwardly in the chair that held him, his limbs sticking out at all the wrong angles, with his head thrown back and his eyes turned up to the whites. He must have been getting the worst of the electric shocks, because his body spasmed and jerked erratically, making him look like an ill-controlled puppet.
'Joker? Joker!' Batman's mind cried out in desperation. Please let him be alright, he's my only chance. 'Joker?'
The body continued to twitch in what looked horribly like death throes, but Joker's voice came through clear and alive. 'What do you want?'
'You're okay?'
'Of course I'm okay. I haven't had this much fun since my ex-girlfriend dropped a live radio in the bath when she found out I was cheating on her.'
It was hard to tell whether this was to be taken as sarcastic or not so Batman decided to ignore it. 'Joker, listen, I think I know how to stop this. Our thoughts are being channelled through Strange, so if we concentrate hard enough we should be able to short circuit the link. Understand?'
'Receiving you loud and clear, Batsy. Oh, so that's Alfred. A bit old to still be walking around on earthly planes, isn't he?'
'Joker, concentrate!'
'I will, I will. Lighten up, Batsap.'
How could Joker be so perky under such an amount of pain, Batman wondered. That communication, the concentration it had required to form intelligible words and sentences had all but exhausted the Dark Knight. His head felt like it was being ripped apart. He was suddenly unsure if he had the strength left to carry out his plan. But of course he had the strength – he would make himself have the strength. Strange couldn't be allowed to get away with what he had done because of Batman's weakness.
The pressure in his head began draining away, giving him more room to think clearly and he realised that the Joker must have started channelling all his mental energy into Strange. With some of the pain alleviated, Batman was able to do the same. Staring hard at the psychiatrist, he focused everything that was being sucked along those wires directly into the short figure, imagining it hitting a road block in his head, building up like water pressure behind a dam. He knew it must have been working because the more water he saw massing behind that dam, the less his head felt like it was being pulled in several directions at once.
Doctor Strange must have felt the change as well because suddenly his eyes flew open, starting from their sockets in blind fear and amazement. He scrabbled wildly at the electrodes on his head, trying to remove them, but he seemed unable to effectively control his movements. Still Batman concentrated his efforts on the psychiatrist, hoping to overload the connection between them enough to break it. Strange let out an animalistic shriek and staggered back, falling over the body of the dead doctor. He laid writhing and moaning on the floor.
The lights in the cavernous room began to fade erratically in and out, crackling in protest as the machine struggled to reach equilibrium once again, unable to cope with the overload of energy. Sparks began to spit from its casing. There was a sudden, audible crack like someone snapping a twig and all the pain disappeared from Batman's head. The connection had broken! The shock of the change left Batman nauseous and disorientated, teetering on the brink of a yawning chasm as the world threatened to turn itself inside out. He managed to ride out the waves of faintness that engulfed him and emerge gasping for breath, but awake and finally in full control of his senses.
But something was wrong. The lights continued to pulse madly, the machine still shuddered and spat sparks and Doctor Strange was screaming, tearing at his face with clawed fingers. Batman stared at the nightmarish scene for a moment, and then he realised what was happening.
'Jo –' No, that wouldn't work. "Joker, you can stop now! The connection's been severed!" He shouted. Then, as that was ignored, louder: "Stop! You're killing him!"
Joker was sat straining forwards in his chair, white-knuckled hands gripping it, the veins in his neck and on his forehead standing out as he channelled a lifetime of hatred and madness into the dying psychiatrist. His scarred face was twisted in an ecstasy of rage, his mouth open in a scream of inhuman laughter. As the grotesque sound reached its crescendo, Doctor Strange gave a final cry and all the lights blew, plunging everything into darkness.