We Are R.E.M. S03 E04 Deadly Pranks

Some one is playing a dangerous game of pranks in school. But REM wont investigate because they don't think this is a real case. They want the BIG one. But when things turn nasty, they have no choice. Meanwhile, we find out some more about Inspector Khattar and the mysterious Lady in Black. It's a only a prank until it turns deadly.