“If the truth comes out they will separate us.” The directorial debut of ‘The Orphanage’ and ‘The Impossible’ screenwriter Sergio G. Sánchez, THE SECRET OF MARROWBONE is a period-piece ghost story about four siblings (played by George MacKay, Charlie Heaton, Mia Goth, and Matthew Stagg) who seek refuge in an old home after the death of their mother, only to discover that the house has another, more sinister, inhabitant.