‘Y. The Embassy informant. They must’ve got to him. He’s the one who told me about how we needed a bug on it.’

‘Is there any way of getting in touch with Y?’ asked Hattie.

‘Frederick.’ I pulled out my phone. Really want to go to that Chinese you recommended. Can you get a booking for me?

He pinged back immediately. No. It’s closed down permanently. Have you not seen the news?

‘G-Force, pull up Sky News. Looking for a story to do with the Chinese Embassy.’ Geraint scanned through the Sky News headlines.

‘Nothing about the Embassy mentioned. There is . . . hang on . . .’ He flashed a photo up onto to the whiteboard. A Chinese man with thin eyebrows and a mole on his left cheek.

‘That’s him. That’s Y.’

Geraint read from his laptop, ‘Yesterday morning the body of Peter Yan was discovered in the Brixton area. Yan had been shot in the head in an apparent mugging gone wrong. Police are investigating. Peter Yan worked as a waiter at the Phoenix Palace restaurant in Mayfair.’

Hattie frowned. ‘Shot in the head. Just like with Frederick’s boss Thatcher. It’s almost certainly Tenebris.’

‘The Chinese won’t even admit he worked at the Embassy.’ Robin rolled his eyes. ‘They could’ve come up with a better cover story than Chinese restaurant waiter.’

‘Eliminating him shows they’re getting desperate,’ said Hattie. ‘We’ve made them nervous enough that they couldn’t risk leaving him alive. We have two days until Peng flies out of here and the Snake goes back underground.’

The Chinese hacker in Watford that Cameron and Robin had interrogated the night before had turned out to be a woman and a big fan of Peng. It became clear that even if she had been working for Tenebris she would’ve turned on them instantly to keep her hero safe. The hacker line of enquiry was officially dead – Cameron and Jake had now ruled out every suspect on the list. We were now pinning everything on unmasking the Snake.

Hattie picked up his iPad. ‘Where are we at with tracing George’s movements out in Switzerland?’

The Switzerland link was still our best lead. If George was hiding the trip from Kate it was not too much of a jump to think he was out there depositing money in an untraceable bank account.