She lay on her bed, but that didn’t help. She made herself a cup of tea, but that had no positive impact either. Eventually, she used the in-house service to send a message to Julie and Suzy, instructing them to book everyone on to an evening flight, the operational teams included.

She went back out into the Tiergarten and walked fast, the events of the morning and all their possible implications churning in her mind. As she passed the Rose Garden for the second time, she pulled out her phone and sent Sergei another message. You there?

She still did not get an answer.

Kate continued on autopilot until she emerged from the Tiergarten just opposite the Holocaust Memorial. She made a point of visiting it on every trip to Berlin, and perhaps its unconscious allure today was a connection with something bigger, of greater importance.

At first sight, it seemed an inconspicuous, underwhelming memorial to the many millions of Jews killed by the Nazis, but as you moved from the low tomb-like slabs of smooth grey concrete on the periphery and into those of monstrous scale in the interior, a sense of the awesome nature of this, the greatest crime ever perpetrated against humanity, became at first unnerving and finally overwhelming.

It was two o’clock in the afternoon by the time she returned to her hotel room. Ian had called three more times, but she decided on a visit to the spa and sauna over responding to any of his messages. She sat next to a very fat, determinedly manspreading German in the sauna and kept her towel tightly wrapped around her. She swam afterwards and felt, in the round, a tiny bit calmer.

She returned to her room, only to find it much colder than she had expected. She came around the corner and saw the window was open, a man sitting in a deckchair outside with his back to her. It was Mikhail. He had a bottle of beer in his hand. ‘I hope you don’t mind. I helped myself from the minibar.’

‘What the hell are you doing here?’

‘You were followed.’

‘Our ops team was confident—’

‘Then they need a kick up the arse. We have been watching you ever since you landed at Tegel. And so have my former colleagues in the SVR. I am sorry you ran into trouble, but it was not of my doing.’

Kate felt acutely vulnerable standing opposite him in her dressing-gown. ‘This is incredibly unprofessional.’

‘Relax. You’re safe with me, as I think you know.’

‘What do you want?’

‘Asylum. As we discussed.’ He picked up a bag on the floor beside him and came into the room. He closed the doors to the balcony, took out a laptop and placed it on the desk.

‘Take a seat.’