The three Gryffindors seemed to be looking for something - they had separated into adjacent aisles. They moved silently towards the ripples of lit wands. The first light belonged to Granger, and Crabbe started towards her with a sick grin. Panicking, Draco seized his arm to stop him. Crabbe swung viciously around, and he thought fast. "Potter!" he mouthed, and Crabbe glared but backed off.