Christian would have loved it.

When I arrived back at the hotel a couple of hours later, I spotted James Caine through the glass wall of the lobby, waiting in his running kit for the lift to the top – the Park Hyatt occupies the thirty-ninth to fifty-second floors of a three-stepped skyscraper, Shinjuku Towers – and I saw how fit he looked.

Not fit for his age, but fit for any age.

He saw me and waved.

And then I felt it.

It was like a train suddenly passing inches from my face. I attempted to stand stock still, yet found that I was still moving. The pavement seemed to shudder beneath my feet and it was as if the air all around me was being dislocated by something of unimaginable force. The train that I could not see continued to roar past my face.

I didn’t understand what was happening. The panic flew in my heart.

Then James Caine was beside me, taking my arm, and I could smell the sweat on his running clothes.

‘We have to get away from all this glass,’ he said.

I made to move into the street where the traffic was slowing to a stop but the pressure of his hand tightened above my elbow.

‘No, not the street,’ he said. ‘That’s where the masonry could fall. We need to go over here. Come on, Tara!’

There was another office building next door, without the great cliffs of glass of our building, and we took shelter under the stone arch of its entrance. Japanese office workers huddled next to us, staring at their phones.

‘We’re going to be fine,’ James Caine said, and we both looked up at the great skyscrapers of Shinjuku and I expected them to tremble and crumble and collapse. The invisible train was still rushing past my face, and the worst thing of all was not knowing how long this would last. I was sick with fear now.

‘It’s not the big one,’ he said. ‘It’s bad but it’s not the big one.’

‘But what’s happening?’

He realised that I truly didn’t get it.

‘It’s an earthquake,’ he said.

And then it was over. The invisible train had passed.

‘There’s an earthquake in Japan every day,’ James said as we walked back to the hotel. ‘Most of them, you don’t even notice. Are you all right?’

Was I all right? No, I didn’t feel as if I was all right at all. There was something wrong with my sense of balance. As I walked, the ground was not quite where I expected it to be when I placed my foot down, and the panic lingered in my heart, the memory of the train passing so close to my face that it felt like it would remove a layer of skin.

‘Japan is the safest country in the world,’ he said, trying to cheer me up.

‘If Mother Nature doesn’t kill you,’ I said.

We both smiled.

‘Are you OK?’ he said as we passed through the walls of unbroken glass into our building. He was still holding my arm. ‘We’re safe now.’