Will moved to object, but it was too late; Henry had already pressed the button. There was a blinding flare of light and a whooshing sound, and the room was plunged into blackness. Tessa gave a yelp of surprise, and Jem laughed softly. "Am I blind?" Will's voice floated out of the darkness, tinged with annoyance. "I'm not going to be at all pleased if you've blinded me, Henry.