Shades of Grey

"Shades of Grey" is the third story in The Book of Falling by Rob Pegler.

Called in to investigate a supernatural disturbance at Downsfield high school, Gabe and Mel come face to face with sixteen-year-old Wilton Grey, a powerful but inexperienced practitioner of the magical arts. Young Will has bitten off more than he can chew, and the entire world may be about to suffer for it.

The story is available here.