S5, E9: MI5 are in charge of protecting Serbian war criminal Niko Grecic before he takes the stand in The Hague. Richard Dempsey, an MI6 traitor, is thought to be looking for Grecic, and Harry wants Dempsey killed. However, Adam and Dempsey had been close friends until Dempsey betrayed him, and when the two confront each other again Adam must decide whether to believe his former friend even if it means disobeying orders.