Wow. Thank you so much for all the reviews, I'm actually completely overwhelmed to get so many and I really wasn't expecting it. You are all amazing and I appreciate every single review more than I can say.

I hope this next part is okay but I'm worried I've let you down - it's taken so long to write and I'm still not as happy with it as I would like to be. Also I've used the word 'sand' 33 times in this chapter and now it's lost all meaning haha.

I'd love it if you can leave a few words. One more part to come.

2.

It takes a few seconds for Cal to remember where he is and even longer to decipher how he got there. His body feels bruised and when he raises his hand to investigate the sharp sting on his forehead, his hand comes away bloody. There's dust on his face and in his mouth. He coughs to try to clear it but ends up inhaling as much as he can get rid of. The lack of fresh air does nothing to appease his discomfort.

He jumps at the sound of someone else spluttering and he lifts his head to see his little brother sprawled across another heap of rubble. His heart pounds with such intensity that he suddenly feels sick. He had no idea Ethan had fallen through as well.

His brother is squinting towards him and Cal frowns back. He hopes the vacant look on Ethan's face is because of his missing glasses, but they were both knocked unconscious and he knows the risks from that include impaired vision.

"Are you okay?"

Ethan pats himself down. "I- I think so."

Cal tries to show his relief but his lips won't form the smile. He didn't know he had a problem with enclosed spaces until now, but the chamber they're in is small and the only way out, the collapsed ceiling, is many feet above them.

"You?" Ethan asks. "You alright?"

Cal delays the answer by helping his brother to remove a large plank which had fallen on top of him. Once Ethan's free, he tries to assess himself so that he can respond, but he's still determining the answer when they hear the static crackle of a radio from beneath a heap of sand and Iain's frantic voice calling them.

Ethan uncovers the radio and quickly responds. "We're in, erm, some kind of basement."

"Are you both alright?"

"I don't, I don't know," Ethan stammers as he climbs to his feet. He looks down at Cal. "Are you alright?"

Cal opens his mouth to reply but another cloud of dust assaults his airway. As he coughs, his attention is drawn to a movement barely a metre from him. Sand is rapidly spilling onto the floor, gushing from a hole in the roof. The pile of sand is growing in size and creeping towards him at a rate he's far from happy with.

He tries to stand but a shooting pain rockets through his ankle. He gasps, pulls a face and remains on the floor. His instinct is to examine his ankle for injury, but when he leans forwards he can see it's concealed beneath various bits of rubble. He clears a few scraps and unearths a larger piece of wreckage, probably a beam, which has fallen flat across his ankle.

It's the beam that needs to go before he can stand, broken ankle or otherwise, so he summons as much strength as he can into his shoulders and gives it a firm shove. It doesn't move. The second attempt achieves nothing. The third doesn't move the beam but judders his ankle so much that he cries out in pain.

Ethan drops next to him. "Cal?"

"I don't think I can move."

"What?"

"My leg!" Cal throws his hand towards his ankle in indication.

Ethan inspects the heavy object. He manages to get his fingers underneath the edge and pulls it as hard as he can. There's no movement.

Cal's gaze flickers to the pile of sand and then back to his brother in time to realise Ethan is having the same thought. The sand has already smothered some of the smaller pieces of rubble and as it continues to fall, there's a great danger of Cal being among the next to get buried. He feels a surge of panic and tries to swallow it back down.

"Iain, Cal's trapped," Ethan says into the radio. "There's sand coming in. How quick can you get to us?"

"We're looking into it," comes Iain's grim reply.

A second wave of fear hits Cal at the same time as a gush of sand. He slams his hand on a nearby brick. "What fucking use is that?"

"Caleb, stay calm," Ethan orders.

"Easy for you to say, you're not the one that's trapped."

Ethan ignores the retort and frowns towards the source of the sand. "We need to think practically," he says. He shrugs out of his uniform jacket and clambers over a heap of bricks. "We need to plug the hole,"

Cal holds his breath as he watches his brother hold his jacket up to the hole. Ethan can barely reach but he balances on his tiptoes and perseveres. Cal wishes he could contribute to the effort, partially because of his height advantage but mainly because he hates how viciously sand is treating his brother.

Ethan's struggling to keep himself upright under the heavy flood of sand and every time he gets near to the hole with his jacket, it knocks him to a lower brick. He's overcome with a violent burst of coughing and stumbles back over to Cal's side to take a deeper breath.

Once Ethan is able to breathe freely again, he turns to Cal and grimaces. "It's not going to work. It's coming down too fast!"

Cal can't dispute the failure, but he feels their only hope of stopping the human hourglass has vanished. The sand has already reached his hips and when he tries to wriggle his uninjured leg he can tell how firmly he's packed in. He knows that once his chest is covered, his breathing could be severely compromised.

He tries to brush some of the sand away but it proves futile as it's pouring as rapidly as he can move it. "Come on!" he yells. He hisses in frustration. "Ethan, do something!"

With one desperate look at the offending hole, Ethan falls to his knees and begins sweeping sand off Cal. But there's nowhere to move it to and Cal is becoming more buried rather than less.

"Ethan, it's no good, you have to free my foot so I can stand."

"And how am I meant to do that?"

"I don't know!" Cal snaps. "But I'm going to die if I stay like this."

Their eyes meet. Cal recognises the expression on his brother's face and that scares him just as much as the threatening sand. It's exactly how he looked when he handed over his test results. He wants to protect his little brother from the pain in his eyes but it's impossible when his own predicament is the current cause.

"Give me the radio," Cal demands. He presses the buzzer. "Iain, we are slowly but surely being buried alive," he shouts into it. "What's going on?!"

"Yeah, we're working on it," Iain repeats. "We are coming to get you."

Cal unleashes a howl of frustration and throws the radio onto the floor. It immediately begins to get covered but neither of them attempts to rescue it. His brother's hand squeezes his shoulder. Cal doesn't know if it was meant to reassure him but his heart is still thudding against his chest.

"It's going to be okay," Ethan says.

On cue, a heavy burst of sand showers down on Cal and he's forced to raise his arms so they don't get buried along with his torso. He's waist deep now and he feels paralysed. From the stress lines across Ethan's forehead, he can tell his fears are shared.

They work in unison, frantic arms shovelling sand to the side. Cal can already feel small cuts on his hands from the abrasive texture but it's nothing compared to the tightening in his chest as the sand piles higher.

Ethan clears a mass of sand and before it's replaced he leans into Cal, pressing his ear against his chest. "Your breathing's a little laboured," he says. "Can you try taking deeper breaths?"

Cal shuffles to try to loosen the sand around his chest. "I'm trying!"

"Come on, breathe with me. In…" He waits a few seconds. "And out…"

"I know how to breathe, Ethan," Cal snaps, "but I've got half a tonne pressing against my chest."

Ethan's lip trembles. "In…" he continues.

Cal shakes his head and tries to palm some of the nearest sand away. There's nowhere to move it to as the whole chamber is filled just as high.

"Out…"

"Ethan, stop!"

Cal can see that his brother's legs are getting buried while he stays still. If the sand is allowed to reach waist height then Ethan will be just as stuck as he is. There's no point Ethan sacrificing his life just to give Cal a few minutes longer. He takes as deep a breath as he can manage and places his hand on top his brother's so that Ethan stops sweeping at the sand.

"Stand up," Cal orders.

Ethan looks at him dumbly. "Well then I can't reach you."

"You're getting nowhere. You need to keep your head as high as possible to give yourself enough time for Iain and the others to arrive."

"No, no," Ethan says. "I need to keep this sand away from you until they arrive."

"You can't," Cal replies. He feels his eyes grow damp. "I'm not getting out of here, but you can."

"No, I'm not giving up." Ethan snatches his hand back and continues to scoop the sand.

Cal wants to tackle his little brother and force him into a standing position, but trapped in the ground, he has to resort to speaking for once, instead of actions.

"Ethan, listen, there's no more you can do for me."

Ethan wipes a hand across his brow, leaving a smear of dirt. "There has to be."

"Even if you continue putting all your energy into keeping the sand off me, it'll only prolong things for a few more minutes." Cal pauses to reclaim his breath. "Just, don't feel guilty, okay? None of this is your fault."

"Stop talking like that, Caleb!"

Cal purses his lips and tries not to cry. He's always hated Ethan referring to him as Caleb but now that it may be the last time, he'd put up with his brother calling him that a hundred times a week. His brother has always been the most important person in his life, whether Ethan would believe it or not, and the thought of never hearing that voice again hurts more than the pressure constricting his lungs.

Cal thinks of all the opportunities, over the last few days, when he could have convinced his brother he'll be there for him throughout his Huntington's but instead remained silent. Now he's about to break that promise before it's even been made. He's never going to be able to repay Ethan for all the things he has done.

Except this. He can save his brother's life as long as he's prepared to die.

"Ethan, leave me. Stand up; keep your head as high as possible and they'll reach you in time, I promise."

"No! No, I'm not doing it. We're both getting out of here alive."

Cal fights to get his elbow out of the sand so that he can brush some off his brother's legs. "Get up otherwise you might not have the choice."

Ethan lets out an uncharacteristic yell of frustration. "Okay," he says, "I am going to stand, but only so I can find another way out."

Cal's heart aches with the bittersweet relief of seeing Ethan get to a safe height. He would much rather his brother stayed by his side until he dies but this is one final chance to protect him. It's about time, he thinks, that he learnt how to behave like a big brother. As he battles to keep his arms free, his eyes remain on Ethan stumbling through the sand to the nearest wall.

Ethan trails his fingers along the flaky plaster as if he's searching for something. He stops but there's barely a second before he throws himself at the wall. He grunts as his shoulder collides with the hard bricks. Although there are no signs of impact, Ethan returns his shoulder to the wall again and again.

Eventually Ethan pauses and glances around at Cal. He gives a tentative smile and a further half-hearted shove. "It's beginning to give."

Cal skips a breath. He feebly pushes away some sand. "You sure?"

"Yeah," he says. "Yeah! We're getting out!"

Cal's dizzy with relief. He's about to reply when out of the corner of his eye he sees another large clout of rubble fall from above. His mouth forms a croaky scream. He barely has time to wonder whether Ethan's movements loosened the rubble, before a stone collides with Ethan's head. His brother falls backwards, irresponsive.

Cal's body jerks with the impulse to get to his brother but all he can do is watch. Ethan's almost horizontal and it doesn't take long before the sand starts piling on top of him. Hot tears escape down Cal's cheeks. His brother could be buried within minutes.

Only one arm remains free but he stretches it as far as he can and manages to reach his brothers thigh. He hits him with all the strength he can muster.

"Ethan!" he cries. "Ethan, wake up!" He shakes his brother's leg. "Come on! Ethan!"

The sand is still pouring in on them and Ethan is out cold. Cal squeezes his eyes shut. If these are their last moments then the only blessing is that Ethan won't be conscious enough to feel what it's like to suffocate, to be buried alive. Cal retracts his arm and allows it to become submerged as well. He prays that it's over quickly.

But then there's a cough and Cal's eyes fly open. His brother's stirring but there's panic written across his face.

"Ethan?"

Ethan splutters. Both of his arms are trapped with the sand and all he can do is lift his head slightly. "I can't… I can't move, Cal," he whimpers.

Cal attempts a deep breath but it feels like the oxygen's been snatched away. "I know. Stay calm, it's going to be fine."

"It's not, is it?"

Cal feels a tear run over his lips. "I don't… I don't know."

There's a pause. The only sound is the trickle of sand.

"Cal?" Ethan says. "I'm sorry for what I said."

"You don't have to be sorry, you idiot," Cal gasps. The sand reaches his chin. He tilts his head backwards so that it doesn't enter his mouth but now it's harder to see his little brother. He takes one last look at him and can see his cheeks are just as damp. "I love you, Ethan."

Ethan wheezes. "I love you too."

Cal's never put much thought into whether he believes in heaven or hell but now he's desperate for there to be some other place. There's so much more he wants to say to his little brother, so many things they still have to experience together. Dying shouldn't be one of them.

He counts his brother's breaths and listens as they gradually slow. Eventually there's silence. Ethan's gone. Cal lets two final tears trickle down his cheek and willingly succumbs to the blackness.