‘Taras has picked them up,’ said Olga Sarapenko. ‘They’re heading out towards the autobahn. He wants you to help him with the surveillance.’ She tossed Maria a walkie-talkie. ‘Channel three. Taras will guide you in. I’m to man the command post here. I’ll liaise between you and Taras and update you on any developments.’

‘Wouldn’t it be better for you to go?’ asked Maria. She suddenly felt very afraid and ill-equipped to deal with the consequences of catching up with Vitrenko. ‘Aren’t you better trained for this?’

‘I’m just a police officer like you. The difference is that you’re a German police officer. Taras thinks that might be useful if things get complicated.’

‘But I don’t know this city …’

‘We’ve got all the geopositioning kit we need to direct you. Use your own car. You’d better go. Now.’

It was dark, wet and cold. Cologne glittered bleakly in the winter evening. It was a straight drive to Lindenthal through Zollstock and Sülz. The radio lay mute on the passenger seat. After ten minutes and as she approached the Stadtwald park, Maria picked it up.

‘Olga … Olga, can you hear me?’

‘I hear you.’

‘Where am I supposed to go?’

‘I’m on the autobahn heading north …’ It was Buslenko’s voice. ‘Head for the Kreuz Köln-West junction and take the A57 and head north. I’ll let you know if we turn off. Olga, guide Maria through Junkersdorf onto the autobahn. Vitrenko’s car is not moving fast, but Maria won’t catch up to us till we stop. Olga … any idea where this takes us?’

‘Hold on,’ said Olga. There was a pause. ‘It looks like Vitrenko’s heading out of the city. Could be that he’s heading back up north. Hamburg.’

‘Unlikely at this time of night,’ Buslenko said. His voice over the radio a universe away. Maria felt isolated, cocooned by the darkness and the thick, sleety rain against the windscreen. How had she got herself into this situation? She had taken so much on trust with these people. Who was to say that they were who they said they were? She shook the thought from her head: they had saved her life; they had found Maxim Kushnier’s body and disposed of it; they had given her ill-planned, half-assed mission some kind of coherence and at least a hint of viability.

Maria pressed the call button of her radio. ‘Tell me where I’ve got to go …’

7.