Miyuki wielded her fishing spear to fend off the beast. Yori clung to Jack in terror.

‘Don’t worry,’ said Jack. ‘It’s just a humpback whale. It won’t attack us.’

‘I’ve never seen an animal so huge,’ Saburo breathed in awe.

The humpback circled the raft, but didn’t approach any closer.

‘It seems to be … studying us,’ said Yori, his fear giving way to curiosity and admiration.

The whale slapped the water with a pectoral fin, sending a shower of spray over the raft. Jack and the others were drenched. Sheltered beneath the canvas bag, Saburo escaped the soaking and laughed. ‘Or else it’s looking for a water fight!’

Then with slow grace the whale arched its back and dived, its fluked tail rising into the air as if waving farewell before slipping beneath the surface. For a moment no one said anything, stunned by their encounter with this benign creature.

Their silence was disturbed by the screech of a seabird. Jack looked up. A white-feathered albatross glided effortlessly overhead. Such birds were believed to be the souls of lost sailors and to kill one was bad luck. But its sighting now was a stroke of fortune. The albatross was taking a westerly course. Jack and the others immediately began to scan the horizon.

‘Birds mean land,’ said Yori excitedly, shading his eyes against the bright glare of the sun. ‘So where is it?’

The shimmering sea yielded up nothing but a distant haze. Jack knew the albatross was a long-distance forager and could fly many miles out from land. But it was late afternoon, so the sighting offered hope. And in a situation as desperate as theirs, hope might be the only thing that carried them through their ordeal.

‘It must be just beyond the horizon,’ said Jack, picking up the makeshift paddles and handing one to Cheng. ‘There’s only one way to find out.’

Kneeling either side of the raft, they began paddling westward while Miyuki and Yori maintained a lookout.

The albatross flew on ahead until it was no more than a speck in the sky.

They rowed after it, swapping with the others when they became tired or their hands too raw. Without any landmarks, it was impossible to tell if they were making headway or just fighting against the tide. But the act of paddling made them all feel as if they were taking charge of their own destiny.

The sun dropped lower in the sky, its rays turning the water golden until it glimmered like silk. But still the sea stretched on. If they didn’t spot land before sundown, they’d be faced with trying to survive the night. Not only would they have to cope with the chilling cold and their mounting thirst but in the dark they might pass by their only salvation.