Jamie stared at the old vampire for a long moment, then got up, walked across the cell, and wrapped his arms round him. Valentin frowned, his eyes flaring with momentary red, then hugged him back, his mouth curling into a small smile.

“You did well, Jamie,” he said, his voice little more than a whisper. “Make sure you find a moment or two to be proud of yourself. It was an honour to fight alongside you.”

Jamie felt his heart swell, and released his grip. He stepped back and met the ancient vampire’s gaze, refusing to be embarrassed by his display of affection.

“I have something for you,” said Valentin, his voice still low. “I’ve thought long and hard about whether I should give it to you, whether it would be better just to destroy it, but I can’t convince myself to do so. So I will do what was asked of me, and let you decide how to proceed.”

Jamie frowned. “What are you talking about?”

The old vampire flew across the cell, withdrew something from the pile of books that covered his desk, and held it out; it was an envelope, creased and tattered and stained with patches of dark red. Jamie took it, frowning with confusion, then felt his heart stop dead.

He recognised the handwriting instantly; he had seen it thousands of times, in Christmas and birthday cards, on notes stuck to the fridge door and scribbled all over the crossword page in the Sunday paper.

To my wife and son, he read.

“What is this?” he asked, his voice low and suddenly hoarse.

“I saw your father,” said Valentin. “Outside Carcassonne, after I defused the missile. He was terribly wounded, but we spoke, and he asked me to give that to you.”

“He was there?” asked Jamie, forcing himself to tear his gaze from the envelope and look at the old vampire. “He was fighting at Carcassonne?”

Valentin nodded.

“Did he make it?” he asked, his throat tightening. “Did he survive?”

The old vampire met his gaze, then shook his head.

Jamie stared. “How did he die?” he managed.

“Well,” said Valentin. “With honour.”

Jamie grimaced, his face screwing up involuntarily as a cocktail of emotions threatened to overwhelm him; there was grief there, a wide, bitter streak of it, but there was pride too, in the fact that his father had clearly decided to try and do something rather than sit idly by as the end of the world approached. He turned the envelope over, took a deep breath, and ripped it open.

“Don’t,” said Valentin.

Jamie looked up. “What?”

“Don’t read it here, Jamie. It’s a private matter between you and him. I don’t want any part of it.”

He hesitated, then nodded and put the envelope in his pocket. “Thank you for bringing this to me,” he said. “I appreciate it, probably more than you know.”

“You’re welcome,” said Valentin. “I hope it brings you peace.”

Jamie nodded again, and walked towards the open front of the cell. When he reached the border of the small room, he turned back. “Goodbye, Valentin,” he said. “Look after yourself.”

The old vampire smiled. “I have never done anything else,” he said. “Goodbye, Jamie.”

Ten minutes later, Jamie slid the sheet of paper out of the envelope and put it face down on his bed.

A large part of him didn’t want to read it, wanted to rip it to shreds and burn the pieces and leave his dad where it had taken months to put him: in the past, where he could do no more harm.

But he knew he couldn’t.

If he destroyed it, he would never stop wondering what it had said.

He took a deep breath, turned over the sheet of paper, and began to read the handwritten lines. When he was finished, he put the letter carefully back into the envelope, lowered his head, and squeezed his eyes shut. The final line danced endlessly through his mind: three simple words, one simple request that cut to the very centre of his being.

Jamie opened his eyes.

“I already have, Dad,” he whispered. “I already have.”

Jamie looked out through the huge double doors of the hangar and saw Larissa standing in the distance, at the point on the wide grounds where the early morning sunlight overwhelmed the shade.

He walked slowly across the tarmac of the landing area and the runway, and on to the soft grass. His head was thick with tiredness, his body weak, but the air around him was cool and invigorating. He stopped beside Larissa, and looked down at the line of shadow as it moved, almost imperceptibly slowly, towards them.

“You did it then,” she said, without lifting her eyes from the ground.

Jamie nodded. “Yes.”

“Why?”

“I don’t know,” he said. “It felt like the right thing to do.”

“As long as you didn’t do it for me,” said Larissa. “You know that—”

“I know you’re going back to America,” he said.

They stood in silence for long, still moments. In the distance, Jamie heard the rumble of an engine as one of the black SUVs emerged from the authorisation tunnel; he strained his ears, and realised that it was all he could hear. Twenty-four hours ago, he would have been able to hear the humming and fizzing of the electrified fences at the Loop’s perimeter, the birds and animals in the forest beyond, and the heartbeat of the girl standing beside him.

Now, he was once again the same as everybody else.

He pulled his father’s letter from his pocket and held it out towards Larissa. She narrowed her eyes, took it from his fingers without a word, and began to read. Jamie watched, waiting silently for her to finish.

She lowered the sheet of paper, and looked at him with tears in her eyes. “Where did this come from?”

“He was at Carcassonne,” he said. “Fighting with the others. He gave this to Valentin to give to me. Before he died.”

“Oh, Jamie,” said Larissa. “I’m so sorry.”

“Thank you,” he said, and nodded. “It’s all right. I’m all right.”

“Have you shown it to your mum?”

“No,” said Jamie. “Not yet.”

“Are you going to?”

“I honestly don’t know,” he said.

She stared at him for a long moment, then returned her gaze to the line of sunlight that was slowly creeping closer and closer to their toes.

“You could come with me,” she said.

Jamie frowned. “What?”

“To Haven,” she said. “You could come with me.”

“I don’t know,” he heard himself say. “There’s so much to do here, so much to sort out. There are vampires that want the cure, and ones who don’t that need tracking down.”

“I know,” said Larissa.

“The Department needs rebuilding again. Kate’s only just woken up, and Matt and Natalia and my mum are all going to go, probably sooner rather than later. Frankenstein’s gone and Valentin’s gone and you’re going to go and it’s all just—”

“I know,” she said. “I get it, Jamie. I really do.”

He nodded. “So what happens now?”

She shrugged. “I have absolutely no idea.”

“So what do we do?” he asked.

Larissa raised her head and smiled at him, a beautiful, brilliant smile, full of life. “Take my hand, Jamie,” she said.

He reached out, and watched her fingers close over his. Then she squeezed his hand and led him forward, into the light.

My love and thanks to Charlie, Nick, Sarah, Mum, Peter, and everyone else who helped turn a dream into a reality. You know who you are.

My eternal gratitude to everyone who has picked up a copy of a Department 19 novel in a bookshop or a library, or downloaded an ebook. The idea that something I wrote is out there in the world, being read by people who could be doing literally anything else with their time, never ceases to be amazing, and humbling.