I tried to piece together the timeline. Mum and Dad had set off on their own research trip – with Yannick, presumably – before we got back. He might have heard about his brother’s tragic death en route or when he arrived in the east of the country. Could he have abandoned Mum and Dad in his grief, or even blamed them for what happened? Might he have handed them over to the kidnappers on purpose? There had been nothing about Innocent in the ransom note or on the phone, but that didn’t mean there wasn’t a link. The police hadn’t been able to find Yannick yet. If he’d been taken hostage too, the note would have mentioned it, surely. And if he’d been released, wouldn’t he have raised the alarm? I smelled a rat! Standing on the dusty step in front of the Mugalia brothers’ office, I spelled my thoughts out to Amelia, only pausing when a cement mixer with the loudest exhaust pipe I’ve ever heard trundled past, blotting out what I was saying.

She brought me down to earth with a bump when it rounded the corner: ‘That racket made more sense than you were making,’ she said.

‘What do you mean?’

‘You’ve no evidence Yannick was involved in the kidnapping. His brother died. He’s gone missing. Your parents employed both brothers and they’re missing too. That’s it – the facts.’

‘Yes,’ I admitted, ‘but until we find him we can’t rule it out.’

‘How are you going to do that?’

‘Marcel,’ I said. ‘He worked with Innocent. So he’ll know Yannick too. He may be able to give us a steer.’

‘Good point,’ said Amelia, and followed it up with something I’ve rarely heard her say: ‘I hadn’t thought of that.’

‘What’s his number?’ I said, pulling out my phone.

‘He gave his card to you, not me,’ she said.

‘Didn’t you see it?’

Looking sheepish, she said, ‘No.’

I couldn’t help grinding my teeth. The one time Amelia’s photographic memory would have been useful, it turned out she hadn’t looked at Marcel’s contact details when he handed them over. ‘Never mind,’ I said. ‘His card is with my stuff at the hotel. Let’s get back there.’

We set off more or less at a run, headed straight for the hotel. But the demo was still going on. Maybe the crowd was quieter now, or didn’t look as intimidating, or perhaps I just thought the risk worth taking to avoid another delay: either way, this time I ignored my better instincts, grabbed Amelia’s hand and ploughed straight into it.

Big mistake.