On the one hand, this is a delicate, detailed portrait of three generations of a very English family. Gathered for a traditional family Christmas in the Cotswolds in 2008, the fracture lines, weak spots and the stong ties that bind them are all elegantly exposed. On the other, there's a sharp, subtle frost wrapped around the tale; a dystopic future reality quietly but inescapably threaded though the story, which chills to the bone.