Lucía manages to join the British Mining Company as a secretary after some very demanding tests. Miss Parker, head of personnel, and Peter, the manager, are fascinated by her exceptional qualities. But Lucía, although happy, has lied both in the interview and to her boyfriend, the Governor, Francisco Martín, whom she wants to marry. Intrigued by Peter, she will soon suspect that things happen at The Company that go beyond the administrative. For their part, the British suffer from a shortage of diesel to transport the mineral from Riotinto. Edward, an undercover spy, wants Peter to return to MI6, but a past trauma prevents him from doing so. Additionally, Peter has become addicted to opium painkillers. The relentless advance of the Nazis in Europe and Churchill's rise to power prompt Peter to embark on a dangerous mission, discovering that the Nazis are behind the fuel shortage. Lucía, who will be directly involved in the war between the two sides.

An Italian spy arrives in Huelva bringing classified information that both sides want. The Nazis go ahead and hide it in the German Consulate. Peter manages to contact the Italian and offers him to leave the country, without being very clear about his loyalties. Lucía, after seeing the war room, discovers that there is a team of spies in La Compañía. The British are going to celebrate the King's feast and Francisco invites Lucia, who fears being fired from her when Peter discovers that she is the governor's girlfriend. This invitation brings to light old secrets that implicate Rocío, Francisco's mother, and Cinta, Lucía's mother: she must prevent Lucía from going to the party with her son. For his part, Schneider appears at the party with Hanna, his daughter, who notices the governor. The English will use the party to get the Italian out of the country and Lucía finds herself inadvertently involved in the mission.