Stranger Things stage spin off, Stranger Things: The First Shadow.The theatre prequel, which is being staged at London’s Phoenix Theatre, is set to start on December 14, with previews having begun this week (November 17).Netflix and Sonia Friedman Productions have shared a production still, featuring a young Henry Creel (played by Louis McCartney) facing down a Demogorgon in a richly coloured, misty setting under a swirling cloud of bats. See the image below.Stranger Things: The First Shadow is set in 1959 and will follow young versions of Jim Hopper, Bob Newby and Henry Creel.