The plan came to Thor after Loki had surrendered his consciousness, drifting silently away from the prison and into the arms of darkness, all his emaciated limbs free of tension and his head lolling against Thor's shoulder.
"Are you sleeping?"
Even as he whispered it, he already knew the answer. The inkcloud of Loki's hair was a fan that framed his face, spread across the pillow's case. On his side, weight propped on one elbow, Thor stared at his younger brother, watching him dream. In sleep, Loki smiled and his fingers twitched where they rested against the quilt. He was no longer a baby, but just barely a boy; his knuckles were still dimpled and his cheeks were still round. In the darkness beyond the bedside candle's warmth, Thor felt their father's presence before he saw or heard him.
"Are you protecting him?" Odin's voice was powerful even when it was quiet.
"Yes." Thor smiled. He was not such a very big thing, himself; he liked the idea of there being someone smaller, someone in need of his protection.
"Are you going to bed, or are you going to protect him all night?"
"I'm going to protect him always."
It was no carefully calculated strategy for permanent escape and evasion, and not all its pieces were penciled in, but leaving Loki here alone was not an option. And this time, for this journey, they would not have the benefit of his magic. By the state of his mortal body, Thor guessed that even to walk would be beyond his brother, much less to run while the posted guards gave chase. Thor could not expect him to assist in any way, but for the first crude leg of this voyage, he would need no assistance from Loki. Cooperation would be enough.
Keeping his brother's body secured to his own with one arm round his middle, Thor reached upward, up above the tight cuffs securing Loki's wrists. The chain links were thick and strong, far too strong for even a particularly powerful mortal man to break, but Thor was still a god. Gritting his teeth and growling with the strain of it, he gripped the chain and yanked until it was uprooted from the concrete ceiling, its fastenings clattering to the floor at the centre of the cell in a rain of rubble.
Loki woke with a jolt and cried out in abject agony; when the length of chain fell, its weight brought down his arms, muscles and joints rapidly forced to bend and move in directions they hadn't for a number of months. Thor's brow furrowed, his heart contracting at the pained expression on the other man's face.
"I am sorry." He eased Loki to the floor, the second son of Odin gagging, brought to spontaneous regurgitation by the extent of his misery. Mjolnir made quick work of shattering the chain, severing Loki at last from its serpentine imprisonment, only two links remaining attached to the cuffs. But the cuffs were bound to one another, and the chain between them was too short to break using the hammer without risking grave injury to Loki's human hands. Total liberation from those shackles would require some thought, and would need seeing to when they had more time. Thor wanted no part of hurting guards who were following orders. He wanted to be well away from the towers before they entered the cell to investigate the commotion.
Winding up, he swung Mjolnir overhead and struck the wall of the cell. A spider's web of fractures branched out from the point of impact, the building's entirety shuddering under its force. The second thunderous blow broke clear through the stone wallwork, and the night wind whistled into the cell, rustling Loki's loose curls. The younger god squinted into it, breathing the first breath of fresh air in a very long while.
Thor's concern regarding guard interference mounted, but despite the noise, no one came. He struck the wall a third time, then a fourth, widening the opening to a gaping hole broad enough for the brothers to pass through. Loki was struggling to stand on useless chalky legs, those limbs trembling and folding beneath him. He was as weak and graceless as a wet fawn, but some things were unchanged.
"This is very typically 'Thor,'" he said, derision dripping from his words. "All smashing and no finesse."
"Do you prefer to stay here?"
Loki's features softened, the spite fading from his expression as he shook his head, his lips and face colourless.
Thor detached his cape from his shoulders, furling the rich fabric around his brother, then gathering him again in a one-armed embrace. With his free hand, he wound Mjolnir swiftly, and once it was spinning quickly enough, he charged across the cell and leaped with his cargo through the opening he had made in the wall. Darkness engulfed them and no arrows sought them. It was too easy.
The night air was cool. Insulated by his power and vitality, Thor felt nothing but refreshed by its briskness against his face, but only moments had passed before Loki was blanketed in gooseflesh and shivering convulsively. His wrists were still bound, but he clutched with bony fingers at Thor's forearm where it crossed his waist. Glancing back over his shoulder, Thor watched the torchlight fade behind them, and spoke then with his mouth against his brother's ear, "Fear nothing. I will take us to lower ground, into warmth and hiding." No response came. Maintaining consciousness was consuming all of Loki's focus.
At the very fringe of the kingdom, where the population rose from the sea, a peninsula arched out and broke into a hook-shaped archipelago of small and tropical islands. The outermost few were surrounded by the blue brilliance of sandy shallows, and the very last, furthest from civilization, was of no greater breadth than Odin's primary banquet hall. Populated only by birds and trees, the island was brief stretch of white beach and a smooth wall of sheet rock hollowed into a varying series of caves.
Thor made his landing in the hard-packed wet sand beneath a cluster of palms, Loki now limp in his grasp. Holstering Mjolnir, he scooped his brother into the more secure cradle of both arms and carried him two hundred paces uphill into the cave with the smallest mouth. The blackness was absolute, but Thor knew he was nearing the end of the cave by the count of his footsteps. He knew it was the safest, the deepest, and the most secretive. He knew the water could not reach the back of it, even in a storm, and he knew no one frequented this place. It had once belonged to them.
Feeling blindly about with one hand, Thor found the rough rope rigging of an old canvas sail they had fashioned their ceiling from, tied in place to block the light from above and keep the cave cool on hot days and dry on wet ones. When he tugged the rope, the sail fell into a heap, and dust billowed, and moonlight spilled into the cave through a smattering of worm and waterholes from far overhead. Through the centuries, the holes had formed through tonnes of rock until at last they had reached the cave, now slanting in tubular blue pillars through the darkness. As he made his way toward their makeshift bed, his boot crushed something dry and delicate, a wreath of twigs.
"You're the dragon." Loki lowered a crown made of boughs regally onto his own head. "I'm the king. Jump out from behind that boulder and scare me, and I will slay you." In richly-coloured clothes, his voice echoing in the hollow corridor of their cave, Loki certainly looked his part. Now that they were nearing pubescence, he always seemed to remain clean and composed while they played, even after rafting for ages to a desert isle and camping in a cave.
Thor was larger, broader, and a wild beast of a manchild, barefoot and barechested with sticks and leaves tangled in his sunbleached mane, a tear in his trousers. His protest was halfhearted: "I am always the dragon." Even as he spoke, he followed his orders, wedging his body between the heavy mound of a stone and the cave's back wall. He crouched there, listening while Loki set the scene, making galloping sounds to stage his approach, interacting with fellow warriors who did not exist. The expansive imagination made him smile, though that expression died on his lips when he recalled his father's admonishment at their disruptive play only days before, scolding them for childish destruction when they were soon to be warriors and kings; Thor knew their days of playing pretend were numbered.
When Loki crept around the face of the boulder, Thor knew he was meant to leap forth and roar and gnash his teeth. Instead, he tackled Loki to the ground, easily immobilizing and disarming him, casting aside his wooden sword. Instead of ferocity, Thor opted for silliness, sitting astride his brother and tickling him. In the struggle, Loki's crown was dislodged and crushed and rolled crookedly away.
"Stop, you fool!" he shouted, shoving at Thor's chest with both hands. "You ruin everything."
There was melancholy in Thor's smile as he stooped to ease Loki onto the bed they had constructed ages ago of stolen palace linens. No one and nothing had bothered it in all the years since its last use, and though they had grown a good deal since last they'd stretched upon it, neither of them had outgrown this place. A moonbeam blanched a spot on Loki's cheek, made that skin even whiter than it naturally was, and another landed over his eyelid. His lashes fluttered as he forced himself to see, to take in their hiding place, and his brow smoothed as recognition dawned.
"Here?" he asked, and Thor nodded, still on his feet, removing his boots. "And then?"
"Focus less on 'then' and more on 'now,' brother. Here we are, safe and warm, dry, with fruit on the trees and fish in the sea." He removed his armor, standing over Loki alongside the bed.
"You will wish we had focused on 'then' when your father's guards are dragging us from bed and hanging you from the ceiling alongside me." Too weak to stand or walk, Loki still had the strength to kick the back of one of Thor's knees while he was momentarily blinded, dragging his tunic over his head. His knee buckled, but he caught himself before he lost balance, and turned to glare at his younger brother. Loki only smiled, pleased with his own mischief.
"Our father's guards didn't so much as open the door as I was smashing through the wall. Perhaps my saving you was part of his plan all along." The air was warm and damp, and even from the minor exertion of undressing, all of Thor's bronzen body was veiled in a sheen of perspiration. When Loki said nothing to disprove his theory, called him no names, Thor knew there was merit in what he had said. Either that, or it was ludicrous and Loki was choosing to hope against hope. "Shove over. The bed will still sleep us both."
Loki surprised Thor, and made room for him without further incident. Despite the fact that it was only blankets piled over rock, the bed was as comfortable as Thor remembered it when he stretched alongside the other man, exhausted by the night's stress and exploits. Eyes closed, he lay awhile in thoughtful silence, only the melodic push-and-pull rhythm of soft waves at the cave's mouth lulling them.
Long beyond the point when Thor had assumed Loki was asleep, the velvety sound of his voice filled the quiet: "How do you know I won't kill you while you are dreaming?"
"I don't," said Thor. The truth in it saddened him. "Go to sleep."