A file of documents describing the detection, arrest and trial of a German agent named Rogerio de Menezes, who was a minor official at the Portuguese embassy in London. The documents in the file include a document sent by Menezes to Lisbon with a hidden message about arms shipments to Turkey and planned allied operations in Greece; messages exchanged with the Portuguese Ambassador asking for permission to arrest Menezes; instructions from the Portuguese government to the ambassador, removing Menezes’ diplomatic protection and turning him over to the British; correspondence to and from the ambassador noting that António Salazar was upset by the case; reports on the interrogation and confession of Menezes; an account of his recruitment by German agents; Portuguese speculation about how he was discovered by the British, including the opening of the diplomatic bag; arrangements for the trial of Menezes, and his eventual sentence to life imprisonment.