Everyone nodded nervously. Facing north, they spread out in a line towards each side of the tiny island. As they moved forward through the thickening mist, they began to lose sight of each other. Cluny, on the far left, could see only Pete through the mist.

Cluny was moving up the steepest edge of the westernmost hill. The sea and thicker fog lay to his left. A tendril of thick fog drifted round him until he couldn’t even see Pete. Nervous, looking hard for the stranger and listening for any sound, Cluny missed his footing and fell. He slid down the slope in a hail of loose stones.

“Oooof!” he grunted, and scrambled up — and saw it!

Through the drifting fog, a ghostly figure stared down at Cluny from an incline! A twisted black shape with a hump on its back and an evil, pointed face with a hooked nose and one enormous eye!

“It’s the phantom!” Cluny screamed. “Help!” The phantom moved towards Cluny, reaching its long, misshapen arms out to grab him!

“Help! Help!” Cluny shouted, cringing from the menacing phantom.

Pete came pounding up through the fog. “What is it!”

“The phantom!” Cluny pointed. “There!”

Pete gulped and shrank back from the grotesque figure. The phantom’s single eye moved, followed him.

Then Professor Shay arrived, and Jupiter and Bob came panting up. As they stared at the ghostly shape, the fog suddenly thinned. Bob cried:

“It’s a tree!”

“One of the cypresses, twisted by the wind!” Professor Shay added.

The hunchbacked phantom was only a twisted, stunted tree trunk with branches bent out like arms. The “head” was a gnarled stump at the top with a hole in it. Fog drifting behind the hole gave the effect of a moving eye.

“Phew!” Cluny said with relief. “It sure looked like the phantom!”

Suddenly Jupiter exclaimed, “Fellows! It is the phantom! Don’t you see? It must be old Angus’s sign!”

“The sign?” Pete asked.

“You really think so, Jupe?” Bob cried.

Professor Shay narrowed his eyes behind his rimless glasses. “By Caesar, I think Jupiter must be right! Search round the tree, boys, for a hiding place! The treasure could be here!”

“I’ll look on the left!” Cluny said.

“I’ll take the right!” Bob joined in.

Professor Shay said, “You climb up above, Jupiter. I’ll look round the base of the rise!”

Pete was left standing alone as the others swarmed round the grotesque little tree. He looked to the right, and then to the left. He looked behind him, and then up the rise.

“Fellows,” Pete said slowly.

They didn’t hear him, or ignored him. They were poking at the thin dirt round the tree and turning over every rock they could find. Professor Shay was probing a crevice with a long stick.

“Fellows,” Pete said again, “I don’t think you’re going to find anything.”

Jupiter stopped scraping the dirt. “What? Why, Second?”

Pete shook his head. “I don’t think old Angus would have used that tree for his phantom sign, guys.”

“What are you talking about, Peter?” Professor Shay snapped. “Why don’t you help us?”

“Look over there.” Pete pointed to the right.

“Up on the slope — it looks to me like two more phantoms!”

Two ghostly shapes loomed in the mist.

“And there.” Pete motioned behind him. “Three more phantoms!”

As the rising wind blew away the thicker mist, more and more of the twisted trees appeared. Everyone stopped digging and looked at them. Professor Shay groaned and threw his stick away.

“They’re all cypresses! Seen from the right angle, almost every one of them would look like some kind of phantom!”

Jupiter nodded sadly. “Pete’s right. There are too many phantom trees for old Angus to have picked one as a sign. Or else —”

“Or else what, Jupe?” Pete asked.

“Or else Angus made a mistake and did pick one to mark the treasure,” Jupiter said. “It would take months and months to dig round all the cypresses! We might never find it!”

“I’m afraid,” Professor Shay said, “we’re beaten, boys.”

“Only if old Angus did hide the treasure on the island,” Jupiter said. “But —”

The stocky boy was interrupted by a sudden shower of pebbles and rocks that rolled down the slope. He looked up. The mist was almost gone now, and he could see another phantom shape standing on the crest of the hill.

“Just another cypress!” Cluny laughed.

“But,” Jupiter said, “a tree can’t make stones roll unless —”

“Unless it can move!” Pete said.

“It is moving!” Professor Shay cried. “That’s no phantom tree, that’s a man up there! You! Stop!”

The figure on the crest vanished. A sound of running carried from the other side of the hill.

“Quick, boys!” Professor Shay shouted. “Stop him!”

He ran up the slope with the boys behind him. From the top he could see a distant figure running hard, headed off to the right as if to circle round to the cove.

“He must have a boat,” the professor said, panting. “Cut him off!”

They turned and raced back down the hill towards the cove. Pete and Cluny soon outstripped the others and reached the cove in minutes. But the fleeing man was nowhere in sight!

“Over there!” Jupe shouted from the higher ground behind them. “To your left!”

The running figure was just disappearing over a ridge to the north of the cove. Pete and Cluny ran in pursuit. Bob and Professor Shay turned off towards the ridge. Jupiter slowly puffed along far behind them.

Bob and Professor Shay reached the ridge first, with Pete and Cluny close behind. A small, narrow beach lay before them at the foot of the ridge. The fleeing man was already in his motorboat. As he headed the boat away from the island, he looked back for a moment, and the pursuers saw his face.

“It’s the man in the green VW!” Bob cried.

Professor Shay stared out at the thin young man with the black moustache and wild black hair.

“Why,” the professor said, “it’s young Stebbins! Stop, you young villain!”

The motorboat moved farther away from the island.

“The young rascal!” Professor Shay roared. “Quick, to my boat!”

They ran again to the cove. On the way they met Jupiter, still puffing towards the little beach! The portly leader of the Investigators looked at them hopelessly as they raced past him going the opposite way.

“Oh, no!” he groaned, and turned to pant after them again.

The lines were untied, the engine was started, and Pete was ready at the helm when Jupiter finally arrived and collapsed in the boat. Pete steered for the open water. The motorboat was only a few hundred yards ahead.

“Full speed, Peter! Catch him!” Professor Shay urged, and shook his fist towards the motorboat. “Stebbins, you thief!”

Still panting, Jupiter sat up. “You know him, Professor? The young man in the VW? Who is he?”

“My former assistant, young Stebbins,” Professor Shay raged. “He was a graduate student over at Ruxton University, a poor young man, and I tried to help him. But he stole from me! He tried to sell valuable historical items from the Society’s museum. I had to fire him, and he was sent to prison for a year!”

The motorboat was much farther ahead now, almost a half a mile.

“We’ll never catch him,” Pete said. “We’re too slow.”

Professor Shay glared towards the now distant motorboat.

“You wondered how Java Jim knew so much about the treasure and the Gunns, Jupiter,” he said. “There’s your answer! I recall now that Stebbins was very interested in the Argyll Queen and old Angus Gunn! He must have escaped, or been paroled. Now he’s up to his old tricks. He’s probably working with your Java Jim, by Caesar! He’s a most dangerous young criminal!”

“Stebbins must have been the one who photographed the journal at Headquarters last night,” Bob decided.