“Place the disk here,” Calculus said, pointing to a depression in the altar’s center.

“Vega plans to use my resonator to activate this,” Calculus whispered. “He could sink ships, collapse cities—hold the world hostage.”

“That’s the same symbol,” Tintin murmured, glancing at the disk. Captain Haddock, nursing a glass of Loch Lomond whisky in the next room, squinted at the disk. His weathered fingers traced the symbols.

Footsteps echoed. Vega emerged from the shadows, flanked by armed mercenaries. “Thank you for opening the door, Tintin. Now, if you’ll step aside…” Vega’s men seized the Eye. But Vega, greedy and impatient, tried to activate it immediately using Calculus’s resonator. He misaligned the calibration.

“Tintin! Someone broke into my laboratory! They stole my geomagnetic resonator—but worse—they left this .” A fax whirred through. It was a crude drawing of a compass rose, but instead of North, the needle pointed to a serpent swallowing its tail.

Calculus, bandaged but cheerful, added: “The magnetic anomaly has dissipated. The world is safe—though my resonator is beyond repair.”

A deep rumble shook the cave. The floor cracked. Steam hissed from the walls.

But the intruders hadn’t thought so. And now Calculus’s resonator—a machine that could amplify magnetic pulses—was in their hands. Within hours, Tintin, Haddock, Snowy, and a grumbling Calculus (who insisted on coming to “protect his scientific honor”) were aboard a cargo freighter bound for the Azores. Their only clue: the disk’s symbols matched a sea cave on the island of Corvo.