Scorpia

gondola drew past, the gondolier singing in Italian to the grinning family of tourists he was carrying. For a second Alex thoughtabout hijacking the gondola. Then he had a better idea.
    He reached out and grabbed hold of the oar, snatching it out of the gondolier’s hands. Taken by surprise, the gondolier shouted out, twisted round and lost his balance. The family looked on in alarm as he plunged backwards into the water. Meanwhile Alex had tested the oar. It was about five metres long, and heavy. The gondolier had been holding it vertically, using the splayed paddle end to guide his craft through the water. Alex ran. He stabbed down with the blade, thrusting it into the Grand Canal, hoping the water wouldn’t be too deep.
    He was lucky. The tide was low and the bottom of the canal was littered with everything from old washing machines to bicycles and wheelbarrows, cheerfully thrown in by the Venetian residents with no thought of pollution. The bottom of the oar hit something solid and Alex was able to use the length of wood to propel himself forward. It was exactly the same technique he had used pole-vaulting at Brookland sports day. For a moment he was in the air, leaning backwards, suspended over the Grand Canal. Then he swung down, sweeping through the open entrance of the water bus and landing on the deck. He dropped the oar behind him and looked around. The other passengers were staring at him in amazement. But he was on board.
    There were very few ticket collectors on the water buses in Venice, which was why there wasnobody to challenge Alex about his unorthodox method of arrival or demand a fare. He leant over the edge, grateful for the breeze sweeping across the water. And he hadn’t lost the motor launch. It was still ahead of him, travelling away from the main lagoon and back into the heart of the city. A slender wooden bridge stretched out over the canal and Alex recognized it at once as the Bridge of the Academy, leading to the biggest art gallery in the city. He had spent a whole morning there, gazing at works by Tintoretto and Lorenzo Lotto and numerous other artists whose names all seemed to end in o. Briefly he wondered what he was doing. He had abandoned the school trip. Mr Grey and Miss Bedfordshire would probably already be on the phone to the hotel, if not the police. And why? What did he have to go on? A silver scorpion adorning a private boat. He must be out of his mind.
    The vaporetto began to slow down. It was approaching the next landing stage. Alex tensed. He knew that if he waited for one load of passengers to get off and another to get on, he would never see the motor launch again. He was on the other side of the canal now. The streets were a little less crowded here. Alex caught his breath. He wondered how much longer he could run.
    And then he saw, with a surge of relief, that the motor launch had also arrived at its destination. It was pulling into a palace a little furtherup, stopping behind a series of wooden poles that slanted out of the water as if, like javelins, they had been thrown there by chance. As Alex watched, two uniformed servants emerged from the palace. One moored the boat; the other held out a white-gloved hand. The woman grasped the hand and stepped ashore. She was wearing a tight-fitting cream dress with a jacket cut short above the waist. A handbag swung from her arm. She could have been a model striding off the cover of a glossy magazine. She didn’t hesitate. While the servants busied themselves unloading her suitcases, she climbed the steps and disappeared behind a stone column.
    The water bus was about to leave again. Quickly Alex climbed out onto the landing stage. Once again he had to work his way round the buildings that crowded onto the Grand Canal. But this time he knew what he was looking for. A few minutes later, he found it.
    It was a typical Venetian palace, pink and white, its narrow windows built into a fantastic embroidery of pillars, arches and balustrades, like something out of
Romeo and Juliet
. But what made the place so unforgettable was its position. It didn’t just face the Grand Canal. It sank right into it, the water lapping against the brickwork. The woman from the boat had gone through some sort of portcullis, as if entering a castle. But it was a castle that was floating. Or sinking. It was impossible to say where the waterended and the palace began.
    The palace did at least have one side that could be reached by land. It backed onto