A new investigation for military policeman Max Rydal: During the hectic weeks before Christmas, the personnel of 26 Section Special Investigation Branch are engaged in shifting their headquarters in Germany. It is not going well. Snow is falling, the heating has failed and tempers are getting frayed. Crime, of course, doesn't stop for the move, and head of section, Max Rydal and his deputy, Sergeant Major Tom Black, are called to investigate a brutal attack on a young boy at a fancy-dress party. Meanwhile a military truck has gone missing, together with its driver, and there's a call for security to be tightened in preparation for the arrival of a high-level chess convention. Max, facing a lonely Christmas on base, is soon caught up in a complex case which offers little light relief - until he is introduced to one of the competing chess players, the glamorous Livya Cordwell.