A serial killer struck again—this time, the girl fought back. Jennifer Wertz used tricks she'd learned from FBI shows to stay alive…and expose the truth. Kids are hollering '6-7' in the classroom.

It was a little after 11:30 p.m. on a Thursday night in downtown Houston. Under the glow of the high-rises, a group of friends were gliding along Buffalo Bayou on scooters – the very image of urban ...