Ianto grabbed Jack's arm and held him back. "It's a swamp," he warned angrily. "He's leading us into a bog."

"Swamp, yes. Secret paths through the swamp. No one else knows it, too dangerous." Serki leered over his shoulder. "Watch out for crocodiles."

Jack met Ianto's eyes and pulled his arm from his grip carefully. "We have to trust him, Ianto. We don't have a choice."

"Fine," Ianto muttered. "But I'm not fighting with a crocodile if you get eaten."

They picked their way carefully between the shallow pools, testing each step for security and slipping often, hurrying along in Serki's sure-footed wake. He loped forwards on all fours, bare hands and feet more tactile and sure than their worn boots, and they turned their faces away when he found worms in the mud. On one of these occasions, Ianto found himself staring down into a shallow pool. "Jack," he hissed. "Jack, there's a face in the water."

Jack joined him and crouched down, stirring the surface with a finger. "They're... Oh my God."

"They're real? Not some..." Ianto trailed off, not knowing what it could be. "There's a real person drowned in the marsh."

"Many dead faces," Serki laughed at them. "There was a battle, years and years past. The dead lay, and the marshes claimed them. Follow the lights if you want to join them. The Dead Marshes... no one comes here. No one but us creepers."

Jack's hand found Ianto's and squeezed it tightly. "Concentrate on where you're putting your feet, ignore the rest of it," he advised. "We just have to get through this."

He nodded and squeezed back, then slipped his hand from Jack's so that they could continue, a safe distance apart.

The way was as treacherous as their guide, and Ianto found that the tussocks of grass which provided their path would just as soon turn an ankle as save them from the water. He was ahead of Jack, so that he could test the way and so that Jack could keep an eye on him, in a reversal of their usual roles, so the splash from behind him came as a surprise, as did the sight of Serki streaking past him. He turned carefully and his jaw dropped with his stomach at the sight of Serki dragging Jack fully out of the water. "Idiot..."

He hurried towards them, as fast as he could, and did his best to ignore the look that Jack was giving Serki. It was just gratitude, or shock. Definitely not curiosity and affection. He dropped to his knees next to Jack and wrapped his arms around him, not caring that they were both wet now as they held each other tightly, with Jack still staring at Serki.

Late that night, as the moon swung back towards the horizon, Jack lay awake with his back to Ianto and the strange device in his hands. He wanted to activate it, to find out if he would be able to hear the song that Serki could, the music that was just on the cusp of his hearing.

"So beautiful..." Serki's voice drifted across the marshes and Jack shoved it back into his bag, out of sight. "Soft and sweet and slow. The song of the stars. And of war."

He sat up and stroked Ianto's shoulder to settle him again when he threatened to wake, then stood and walked across the island to Serki. "I think you fell through the Rift somewhere," Jack told him softly. "Maybe in Egypt, maybe in the Basque Country... maybe even in Cardiff. Was that where you heard it, Serki?"

"Not Master's business," Serki sulked, turning away from him. "We are Master's now, weren't Master's then."

"Were you one of the ones who was brought back and escaped Torchwood, back in the old days?" Jack crouched down close to him. "Maybe I can give you a name, even. I know who you are... Andrea."

"Andrea... And... Andy..."

"That was your name, wasn't it?" Jack knelt down and spoke gently. "You were six years old when you went missing. Everyone believed you'd been murdered, but there was no evidence. Torchwood made sure of that, because we knew. And I always believed that you'd come back, on that spike twenty years ago, but we never found you. Andrea?"

Jack still had a photo of her on his desk, the little girl whose grieving parents he'd lied to so many times. Just for a moment, he could see her still in the ravaged body, in the brilliant smile she gave him.

They set off again as soon as it was light enough, and pressed on as fast as was safe. Jack could feel Ianto's watchful gaze on him, but couldn't find anything to say to bridge the gap between them. Ianto wouldn't understand, couldn't understand what it felt like to carry the safety of the world, and what it felt like when your failures came back twenty years later. He wasn't old enough to have twenty-year-old failures and, for the first time, Jack felt bitter about that.

Darkness pressed down within him, and the meagre light that got through the heavy clouds did nothing to dispel it. There had to be something he could do to save Andrea from this existence, to bring her back to herself.

He was so absent, lost in his own worries, that the first shriek from above them shook him into a state of confusion, and it took Ianto to drag him under the cover of a scrawny bush. "Lashimi," Ianto hissed. "Flying Lashimi."

Jack nodded and craned to look up, then tucked himself back under. "We must be getting close."

"What, like we were in Ely?" Ianto shook his head. "Let's hope it leaves quickly."

Jack nodded and closed his eyes. He could almost hear the song now, a quiet whisper that was calling to him. If he activated the device, he could hear it properly, join the song...

Ianto's hand closed around his, and Jack glanced at him to see his worried expression. "Okay?" he asked quietly.

"Fine." Ianto shifted closer to Jack and kissed him chastely, then held him tighter. "Stay with me, Jack."

He couldn't reply, but he let Ianto hold him and curled into his protection.

The evening was drawing on by the time they reached the top of the cliffs that overlooked the Red Sea. When Jack had been here last the sea was tranquil, a place of peace for holidaymakers who could afford it, most of them taking a break from archaeological digs among the pyramids. No speedboats, no warships, just yachts moored up as a luxury home away from home.

Now, the scene was quite different. The wrecks of warships and fishing boats littered the coast where they'd drifted after they were destroyed, and patrol boats steered between rotting hulks further out. Close to the far coast there was the shining roof of the spaceship, their final goal, half submerged to provide an underwater city for the Lashimi army, and the coast behind it swarmed with figures and half-constructed buildings. Ianto swore softly and Jack nodded his agreement. "Straight across and dive?"

Ianto swallowed and leaned over further. "There's a fishing boat down there that looks... merely leaky." He glanced back at Jack and smiled. "And I can see a way down."

Down proved to be less of a problem than he'd thought, as the cliff gave way beneath him and he tumbled down towards the water.

The world ended in Jack's eyes as he dropped down the cliff behind Ianto, heedless of bruises and cuts gained from his hasty descent down the slope. All he knew was that Ianto was still at the bottom of the cliff, half in the muggy water – again. And this time he was Jack's to lose.

He dropped next to Ianto and hauled him out of the water, laying him out on the rocky beach at the very base of the cliff and tapping his cheek. "Ianto, wake up. Come on, please?"

His reward was a soft moan, and Ianto raising a hand to rub his head. "I think I have concussion."

"You're not allowed to have concussion," he chided, mouth on auto-pilot as his brain dealt with the relief. "We have to save the world."

"We always have to save the world," Ianto pointed out. He opened his eyes and smiled up at Jack, accepting his help to sit up. "You look worried."

"I was worried."

Ianto's lips were chapped and dry, but gentle and familiar when they met Jack's in a soft kiss of reassurance. He choked into it and held Ianto tighter, seizing the moment, possibly the last they had, then broke away to look past him at the dark waves. "I'd rather you didn't come with me."

"I know."

"You're going to anyway," he guessed.

Ianto found his hand and held it tightly. "Someone has to watch your back."

He looked around at him and smiled tightly. "That boat."

"Master, no!" Andrea grabbed at his arm as she arrived, panting. "No, they will find you and take it. You cannot go that way."

"I have to get in there, Andrea." Jack turned to face her and kept hold of Ianto's hand. "We have to use it to destroy them, it's the only way."

"No!" She sobbed, pawing at his arm. "There's another way, another path."

"There's another way into their base?"

"Yes." She looked beyond them, out to the spaceship, and then back to Jack. "There's a path, an old path, and a secret path. Stairs, down down into the Earth, and a tunnel."

"A tunnel into the base?" he checked. "But they must know about it."

"Know it, some know it. But old, they forget, forget what is real and what is a lie. We found it." She looked proud and Jack reached out to squeeze her shoulder.

"Can you show it to us?"

"Jack, this sounds like a trap," Ianto warned, "we're going to walk into a trap."

He gestured at the sea beyond them. "That looks like a trap. A tunnel they've forgotten sounds like a better chance. Andrea, you can show us the way?"

"Yes, Andrea show. Good Andrea."

"Good Andrea," he agreed. "Show us the way to their base."