‘Of course,’ Emer said. ‘I know what I saw, Dee. She walked into that pub and when I followed her a few minutes later, she wasn’t there. The only possible place she could have gone was behind the bar and into the back area that’s not open to the public.’

‘Did you get the name of the pub?’

‘It was in a place called Wapping,’ Emer said. ‘Near Tower Bridge and Limehouse. I’ve googled it obsessively ever since.’

‘I know Wapping,’ Dee interrupted. ‘And I know most of the pubs there as well. Which one?’

‘It’s called the Town of Ramsgate.’

‘Right.’ Dee grabbed her bag and stood up.

‘Where are you going?’ Emer asked.

‘You mean where are we going,’ Dee said. ‘To Wapping, of course.’

‘So you believe me?’ Emer said, standing up as well.

‘I don’t know what I believe,’ Dee said. ‘But I know there’s only one way of finding out for sure if that woman is your sister. We’re going to the Town of Ramsgate now and we’re going to find out who she is.’

‘Hang on.’ Emer put her hand on Dee’s arm. ‘She can’t see me. That’s why I need you. If she sees me, she’ll try to run away again. If that happens, I may never get to find out if she could be Kitty.’

‘You can stay outside.’ Dee walked up the steps from the cellar bar into the searing London sunshine. On the news the other night, they’d said it had been the hottest summer on record. Something so blindingly obvious she’d wondered, at the time, why anyone had considered it a newsworthy fact. Midway into September and, so far, the heat had shown no sign of abating. She headed towards the Tube station but changed her mind. The thought of being stuck beside so many other sweaty, overheated bodies didn’t appeal to her. Besides, what was the point of getting paid ridiculous sums of money for taking part in fluffy TV shows if you couldn’t treat yourself every now and then?

‘We’ll get a cab,’ she told Emer. ‘Follow me.’

She led her cousin around the corner onto Savoy Place, where she hailed the first black cab she saw and gave the driver the name of the pub in Wapping. Dee didn’t know if this was a sensible idea or not, but she knew it was the quickest way to prove to Emer that the woman she’d seen on the Tube couldn’t be her dead sister. While the cab crawled through the early evening London traffic, Dee got Emer to tell her everything she remembered about the woman.

‘Kitty had a condition called heterochromia,’ Emer said. Then, when Dee frowned, ‘Her eyes were two different colours.’

‘Like David Bowie?’