Lost in the Game (TV series)

A group of teenagers receive mysterious invitations to attend a summer camp. At first glance it appears to be a regular survival camp where the kids take on various physical challenges, but one by one some of the children are secretly taken to a hidden part of the camp. While the others think they've been sent home, the chosen few are introduced to an incredible virtual reality game where they face new challenges in the Middle Ages. Before long, those left behind begin to get suspicious, wondering what's really happened to their friends and why the camp staff are so secretive about the strange man living in the mansion in the woods. - IMDb