A pupil waits in the courtyard of a primary school on September 3, 2013 in Paris, on the first day of school. More than 12 million pupils went back to school today in France. AFP PHOTO / MARTIN BUREAU (Photo credit should read MARTIN BUREAU/AFP/Getty Images)
A couple suspect their young child might be in danger after playdates with a new school friend. His family soon become an object of dislike, anger and finally outright fear, with tragic results.