"WWWWWWIIIIIILLLLLL!"

Will was surprised to find he'd dozed off again. He awoke, disoriented and with no idea how long he'd actually been asleep, as a dull, far-off vibration roused him. He couldn't pinpoint what it was, and in any case the cold, hard reality of the choice to go into the Deeps came flooding back to him. It was as if he'd awoken into a nightmare.

He was Imago crouching by the well, inclining his head toward the sound, listening. Then they all heard it plainly; the distant rumbling grew louder with every second until it began to reverberate around the chamber. At Imago's direction, Will and Cal shimmied over to the opening in the floor and readied themselves. As they both sat with their legs dangling from the edge, beside them Imago was leaning his head and shoulders into the well, hanging down as far as he could.

"Slows around the corner!" they heard him shout, and the noise grew more and more intense, until the whole chamber was vibrating around them. "Here she comes. Bang on time!" He pulled himself out, still watching the tracks below as he kneeled between the boys.

"You're sure this is what you want?" he asked them.

The boys looked at each other and nodded.

"We're sure," Will said. "But Chester…?"

"I told you, don't worry 'bout him," Imago said with a dismissive smile.

The chamber was shaking now with the sound of the approaching train, as if a thousand drums were beating in their heads.

"Do exactly as I say — this has to be timed to perfection — so when I say jump, you jump!" Imago told them.

The chamber filled with the acrid taint of sulfur. Then, as the roar of the engine reached a crescendo, a jet of soot shot up through the opening like a black geyser. It caught Imago square in the face, spraying him with smut and making him squint. They all coughed as the thick, pungent smoke flooded the Cauldron, engulfing them.

"READY… READY…," Imago screamed, pitching the backpacks into the darkness below them. " CAL, JUMP!"

For a split second Cal hesitated, and Imago suddenly pushed him. He dropped into the well, howling with surprise.

"GO, WILL!" Imago screamed again, and Will tipped himself off the edge.

The sides flashed past, and then he was out and tumbling into a vortex of noise, smoke, and darkness, his arms and legs flailing. His breath was knocked from him as he landed with a jarring crunch, and a pure white light burst around him, one he couldn't even begin to understand. Points of illumination seemed to be leaping over him like errant stars and, for the briefest of moments, he really wondered if he'd died.

He lay still, listening to the percussive beat of the engine somewhere up ahead and the juddering rhythm of the wheels as the train picked up speed. He felt the wind on his face and watched the long wisps of smoke pass above him. No, this wasn't some industrial heaven; he was alive!

He resolved not to move for a moment while he mentally checked himself over, making sure he didn't have any broken bones to add to his already burgeoning list of injuries. Incredibly, other than a few additional grazes, everything seemed to be intact and in working order.

He lay there. If this wasn't death, what was the bright, fluxing light he still saw all around him, like a miniature aurora? He pulled himself up onto one elbow.

Countless light orbs the size of large marbles were rolling around the gritty floor of the car, colliding and rebounding off one another in random paths. Some became trapped in the runnels in the floor and would dim slightly as they touched, until they became unseated and scampered off on their ways again, flaring into brilliance once more.

Then Will looked behind him and found the remains of the crate and the straw packing. It all became clear. His fall had been broken by a box of light orbs, which had smashed open when he landed on it. Thanking his luck, he felt like cheering, but instead helped himself to several handfuls of the lights, stuffing them into his pockets.

He got to his feet, bracing himself against the motion of the train. Although foul-smelling smoke streamed thickly around him, the loose orbs lit up the car to such effect that he was able to see it in detail. It was massive. It must have been nearly a hundred feet long and half that in width, much larger and more substantial than any train he'd ever seen Topsoil. It was constructed from slablike plates of iron, crudely welded together. The side panels were battered and rusted away, and their tops worn and buckled, as if the car had seen eons of hard use.

He dropped down again and, his knees grinding in the grit on the floor, the movement of the car buffeting him around, he went in search of Cal. He came across several other crates made from the same thin wood as the one he'd landed on, and then, near the front of the car, he spotted Cal 's boot propped up on another line of boxes.

" Cal, Cal!" he shouted, crawling frantically toward him. In the midst of a mass of splintered wood, his brother was lying still, too still. His jacket was splattered with a wet darkness, and Will could see there was something wrong with his face.

Fearing the worst, Will shouted even louder. Not wanting to knock against Cal in case he was badly hurt, he clambered rapidly across the top of the crates alongside him. Dreading what he was about to see, he slowly held a light orb up to Cal 's head. It didn't look good. His face and hair were slick with a red pulp.

Will reached out gingerly and was touching the watery redness on his brother's face when he noticed the broken green forms scattered around him. And there were seeds stuck to Cal 's forehead. Will drew back his hand and tasted his fingers. It was watermelon! At Cal 's side was another damaged crate. As Will shoved it away to make more room, tangerines, pears, and apples spilled out. His brother had evidently had a soft landing, smashing into crates of fruit.

"Thank goodness," Will repeated as he shook Cal gently by the shoulders, trying to stir his limp form. But his head flopped lifelessly from side to side. Not knowing what else to do, Will took his brother's wrist to check his pulse.

"Get off me, will you!" Cal yanked his arm away from Will as he sluggishly opened his eyes and moaned self-pityingly. "My head hurts," he complained, rubbing his forehead tenderly. He brought up his other arm and glanced bemusedly at the banana in his hand. Then he caught the fragrant smell of the lush fruit all around him and look uncomprehendingly at Will.

"What happened?" he shouted over the din of the train.

"Lucky duck, you fell in the restaurant car!" Will chuckled.

"Huh?"

"Doesn't matter. Try to sit up," Will suggested.

"In a minute." Cal was groggy but otherwise appeared to be unharmed, except for a few cuts and bruises and a liberal dousing of melon juice, so Will crawled back over the crates and began to investigate. He knew he should be retrieving their backpacks from the cars in front of them, but there was no hurry. Imago had said it would be a long trip and, anyway, his curiosity was getting the better of him.

"I'm going to…" he shouted over at Cal.

"What?" Cal cupped a hand to his ear.

"Explore," Will motioned.

"OK!" Cal yelled back.

Will scrambled through the weird sea of light orbs at the rear of the car and pulled himself up on the end panel. He peered down at the coupling in between the cars and the polished sheen of the well-used rails shooting hypnotically underneath. Then he looked across to the next car, only a few feet away and, without stopping to think, hoisted himself over the edge. With the motion of the train it was awkward, but he managed to reach across and straddle both end panels, then had no option but to jump.

He dropped into the next car and rolled uncontrollably over the floor until he came to rest against a pile of canvas sacks. There was nothing much of note here except for some more crates halfway down, so he crawled to the back of the section and got to his feet again. He tried to see to the very end of the train, but the combination of smoke and darkness made this impossible.