He wasn’t expecting her to shove him to the ground and shout, "Protego." A jet of staticky purple light bounced off the shimmering bubble that had formed around them. She grabbed him around the waist and rolled them behind a parked car. She peeked around the corner, and another jet of purple whizzed by them. This one hit the building behind them; a six-foot circle in the brick wall decayed and crumbled into dust. 