Grant said something encouraging. Prabir nodded dully. There was a bar code engraved in the plastic; any pigmentation it had once held was gone, but the ridges still felt sharp, the code could still be read. The numbers wouldn’t mean a lot without matching computer records, but they’d probably be sequential. He delved around in the same spot, and his fingers hit another slab.

They left the hut with twelve preserved specimens: eight adults and four larvae. Prabir looked around, getting his bearings.

He turned to Grant. ‘You might as well go back to the boat now. I’ll follow you in a little while.’ He handed her his backpack, in which they’d placed all the specimens. She accepted it, but remained beside him, waiting for an explanation.

He said, ‘I want to visit my parents’ grave.’

Grant nodded understandingly. ‘Can’t I come with you? I don’t want to intrude, but we should be careful.’

Prabir pulled his shirt over his head, mopped his face with it, then held it bunched at his side to conceal his hand as he switched off the mine detector. He tried to compose his face into an appropriate mask.

He said, ‘Look, how many snakes that size can there be in this area? I’ll be fine. You might as well start working on the samples. I just want to be alone here for a few minutes.’

She hesitated.

‘Is that too much to ask?’ he demanded. ‘I’ve given you everything you wanted. Can’t you show some respect for my feelings?’

Grant bowed her head, chastened. ‘All right. I’m sorry. I’ll see you back there.’ She turned and headed across the kampung.

Prabir made his way around to what he thought was the storage hut. But he didn’t trust his memory, he had to be sure. The door had fallen away; he squeezed through the vines. When his eyes had adjusted to the gloom, he saw the two life jackets hanging on the wall.

He walked out of the hut and headed for the garden.

Suddenly the device on his belt started chanting, ‘Mine at seventeen metres! Mine at seventeen metres!’ He stared down at the machine: a red arrow was flashing on its upper surface, pointing to the hazard. He flicked the ON switch back and forth; it had no effect whatsoever. You couldn’t turn the fucking thing off. All he’d done was stop it wasting power by showing its usual reassuring green light.

He heard Grant call his name from a distance.

Prabir backed away until the detector fell silent, then he shouted in a tone of light-hearted exasperation, ‘It’s all right! I knew there’d be mines here! The detector’s working, and I’ll stay well clear of them! I’ll be fine!’

There was a long pause, then she shouted back reluctantly, ‘OK. I’ll see you on the boat.’

He waited a couple of minutes to be sure that Grant was gone, then he unclipped the detector and tossed it away towards the centre of the kampung. He’d noted the direction the arrow had pointed. He was very tired, but there was nothing left to do now. He turned and started walking.

Something sharp pierced his right shoulder. He felt the skin turn cold, then numb. He reached back and pulled it out. It was a tranquilliser dart.

He didn’t know whether to laugh or to weep with frustration. He looked around for Grant, but he couldn’t see her. He called out, ‘I weigh seventy kilograms. Do the arithmetic. You don’t have enough.’

She shouted back, ‘I can blow a hole in your knee if I have to.’

‘And what would that achieve? I’d probably bleed to death.’

Grant showed herself. She was at least twenty metres away. Even if she was capable of tackling him to the ground, she wouldn’t stop him with anything but a bullet before he could reach the mine.

She said, ‘Maybe I’ll risk that.’

He pleaded irritably, ‘Go back to the boat!’

‘Why are you doing this?’

Prabir rubbed his eyes. Wasn’t it obvious? Wasn’t the evidence all around them?

He said, ‘I killed them. I killed my parents.’

‘I don’t believe you. How?’

He stared at her despairingly; he was ready to confess everything, but it would be a slow torture to explain. ‘I sent a message to someone. A woman in New York, a historian I met on the net. But I was pretending to be my father, and what I said made him sound like an ABRMS supporter. The Indonesians must have read it. That’s why they flew over and dropped the mines.’

Grant absorbed this. ‘Why did you pretend to be your father?’

‘He wouldn’t let me tell anyone my real age. He was paranoid about it—maybe something happened to him as a child. But I didn’t know how to pretend to be anyone else, and I didn’t know how to say nothing at all.’

‘OK. But you don’t know that the message was intercepted, do you? They might have dropped the mines anyway. It might have all been down to aerial surveillance, rebel activity in the area, deliberate misinformation from someone. It might have had nothing to do with you!’

Prabir shook his head. ‘Even if that’s true: I heard the plane come over, and I didn’t warn them. And it was my job to weed the garden, but I went swimming instead. If I didn’t kill them three times, I killed them twice.’

Grant said, ‘You were nine years old! You might have done something foolish, but it was the army who killed them. Do you really imagine that they’d blame you?’

‘I was nine years old, but I wasn’t stupid. After I’d sent the message, I knew what I’d done. But I was too afraid to tell them. I was so full of guilt I went and poisoned one of the butterflies, to try to fool myself. To make myself believe that was why I felt so bad.’

Grant hesitated, searching for some escape route. But she had to see that there was none.

She said, ‘However much it hurts, if you’ve lived with this for eighteen years, you can keep on doing it.’

He laughed. ‘Why?What’s the point? Madhusree doesn’t need me any more. You know why I came after her? You know why I followed her here? I was afraid she’d work it out. I was afraid she’d find something here that would tell her what I’d done. I wasn’t trying to protect her. I just wanted to keep her from discovering the truth.’

‘So how am I going to explain your death to her?’

‘As an accident.’

‘I’m not going to perjure myself. There’ll be an official inquiry, it’ll all come out.’

‘Are you blackmailing me now?’

Grant shook her head calmly. ‘I’m telling you what will happen. That’s not a threat, it’s just the way it will be.’

Prabir covered his face with his arms. The prospect seemed unbearable, but maybe it would help Madhusree put his death behind her if she understood that she owed him nothing. He hadn’t acted out of love for her, or some sense of duty towards their parents. He hadn’t even been protecting their shared genes. Everything he’d ever done for her had been to conceal his own crime.

He turned and started walking towards the minefield. Grant shouted something, but he ignored her. A rain of darts hit his upper back; he lost all feeling after the fourth or fifth, he could no longer count them. He began to feel slightly giddy, but it didn’t slow him down. Grant still had no chance of catching up with him.

He felt a sting on the side of his right leg, like a hot sharp blade passing over the skin. He lost his footing, more from surprise than from the force of the bullet, and toppled sideways into the undergrowth. With his shoulders paralysed he had no strength in his arms: he couldn’t right himself, he couldn’t even crawl.

A minute later, Grant knelt beside him and plucked out the darts, then helped him to his feet. He was bleeding almost as much from the barbed-wire shrubs as from the grazing wound she’d made in his leg.

She asked, ‘Are you coming back to the boat now?’

Prabir met her eyes. He wasn’t angry with her, or grateful. But she’d robbed him of all momentum, and complicated things to the point where it would have been farcical to keep opposing her.