A file of correspondence and memoranda concerning the arrest and interrogation of Luis Calvo, a Spanish journalist accused of involvement in German espionage. The documents detail the initial suspicions about Calvo; the arrangements for his arrest; his interrogation; diplomatic protests by the Spanish government; a debate over whether to open the Spanish diplomatic bag; the threat of retaliation by the Spanish; the obtaining of a confession from Calvo; and further targets for investigation as a result of the confession.