He heard the spell before he saw the caster, but when he did his heart leapt in his chest and he pointed his own wand.

"Expelliarmus," he snapped, and the spell shot off and - there it was. Greengrass' wand shot out of his hand and into the space between them, and Greengrass might have been able to run with the hope of grabbing it before Billy reached him, but Billy still had his wand raised and his expression was plainly not friendly.

He stepped forward once, and then again, and then again, and then Billy was suddenly less than fifteen feet from the other man, narrowed eyes watching his every move. "Now you're going to sit down, and you're not going to do anything," he ground out, jaw clenched tightly.

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