‘Only in a political sense,’ snapped Miss Tefeidiad over her shoulder, before turning a slightly less than reassuring smile on me. ‘We remember your lot when they first started, and a more arrogant collection of . . . gentlemen . . . you will never meet. But we have long memories that go all the way back, you see, back to when your beloved Thames was still scuttling around with his tongue jammed up a Roman backside.’

‘We used to get heads,’ said Corve. ‘The druids used to throw them in along with the other offerings.’

‘Oh yes,’ said Miss Tefeidiad. ‘You got some respect in those days.’

‘Not that we’re looking for heads these days,’ said Corve. ‘We’ll take cash or goods in kind.’

‘So when your lot got themselves all massacred or whatever,’ said Miss Tefeidiad, ‘we weren’t exactly crying into our tea. And I have to say that we’ve got a little bit used to managing our own business in recent years. So, it’s not that we don’t like visitors . . .’

‘We love visitors, really we do,’ said Corve. ‘Liven the place up.’

‘But I think we’re going to have to insist on certain minimum standards of navigational etiquette in future.’ Miss Tefeidiad gave me an expectant look.

‘Sure,’ I said. ‘Stakeholder engagement is a vital part of our modernisation plans going forward.’

‘Look,’ she said, ‘do you want your girlfriend back or not?’

I wanted to tell them that she wasn’t actually my girlfriend and that they better release her before her mother, goddess of the important bit of the Thames, found out they were detaining her and came over to have words. But my life is complicated enough these days and I try not to make things more difficult for myself.

‘Yes, please,’ I said.

Miss Tefeidiad nodded and then looked over at Corve who got to her feet and went to the top of the tree-root stairs. I got up and followed to look over her shoulder.

‘Bev, love,’ called Corve. ‘Your ride’s here.’

She walked out of the pool stark naked – except for the lavender full-body neoprene wetsuit and a Tesco bag wrapped around her hair to keep it dry. She glared at Corve, and then turned her black eyes on me, her full lips twisting into a half smile.

‘You took your time,’ she said.

‘I’ve been busy,’ I said.

Beverley turned to Miss Tefeidiad. ‘Can I have my bag back?’

A purple sausage bag came flying out of the dark interior of the VW. Beverley grabbed it out of the air and slung it over her shoulder.

‘And I believe this is yours,’ said Corve and handed Beverley her phone. ‘Bit of a revelation, that,’ she said. ‘We didn’t know they made them waterproof – very handy.’

‘I can’t be doing with those things,’ said Miss Tefeidiad and sniffed.

Behind her, Corve made a face.

‘Laters, ladies,’ said Beverley and, grabbing my arm, urged me away.