‘Oh my God, the boat’s not here!’ Dora gulped in air and water, making herself accidentally choke, and gasped dramatically for breath.

‘Calm down, Dora,’ instructed Karl.

He forced her to lie on her back and float. ‘Floating stops you swallowing air and helps calm the panic,’ he explained to Ariadne. ‘She’ll be all right now. I’ll go and investigate.’

He swam further away from the cave, grateful at least for calm seas. As luck would have it, the other tourist boats had already left, so there would be no one to call for help. The risk would be if there was a current or rip tide not visible to the eye. He looked up at the cliffs beyond the caves. There would have to be some way of climbing them.

To the left of the cave, the sea was completely empty.

He swam slowly, keeping himself very much under control, round a small headland to the left.

There was the boat!

Their skipper had moored out of sight of any prying tourists and helped himself to a large slug of ouzo, the evidence of which was still in his hand as he snored happily away.

Karl swam up to the boat and climbed up the rather rickety ladder at the back, strode across the deck and whipped the bottle out of the sleeping skipper’s grip. ‘For God’s sake, man, what the hell do you think you’re doing?’

The captain woke in a daze to find he was being berated by an angry, white-haired old man with an expression like thunder, and rubbed his eyes. Surely Zeus was just a legend?

Furious though she might be, Dora had never been more grateful to see anybody when the boat appeared in the cove.

Ariadne shinned up the ladder, full of youthful energy, and held out a hand to help Dora.

‘Is she all right?’ asked Karl anxiously.

Ariadne grinned up at the professor. ‘I think she’s just disappointed about the goddess.’

They refused the beers the captain offered them on the way back – though Dora would have dearly loved to accept – on the grounds it would encourage him.

‘So,’ Dora said, looking round at the other two as they motored towards the quayside, ‘maybe it wasn’t the statue after all. But what the hell do we do next?’

‘I’ve done something rather stupid,’ Moira confessed to Nell, when she bumped into her in the little supermarket behind the hotel.

Nell put down her shopping basket, which contained a large container of still water and a rather delicious-looking sandwich plus some mosquito repellent, a plug-in anti-mosquito device with little blue tablets and a packet of those coil things you burn which the Italians call spirale.