Federico, grandfather of Luis Madero, professor of history, is assassinated in Bolivia while trying to protect a secret of great value. Camila Alvarez is forced to give the bad news to Luis.

The official story of the pendent of a thread to the first page of the manuscript of Mariano Moreno with what was "The Revolutionary Plan of Operations."

In order to avoid that "The Revolutionary Plan of Operations" reverses the story, members of The Lodge will be ahead of the steps that Luis and Camila travel in the search of the 3rd page.

Luis Madero meets with his father and begins to truly believe that the family has the mission of seeking and safeguarding the secret of "The Revolutionary Plan of Operations."

Involved more and more with the investigation, Madero tries to convince Ugarte to authorize him to continue. Camila identified a dark business and The Lodge infiltrated an agent into Luis' life.

The student Faletti joins the investigation and together with Álvarez they go after the steps of the Castelli track. Basualdo is encouraged to defend the legacy as of place.

In order for the document to stop being a threat, it must first appear. Luis, Camila and the new assistant Falsetti embark on the search for a new track, that of Belgrano.

Ugarte begins to suspect. The double face of Basualdo begins to come to light. Luis's father helps him on the Monteagudo track. Camila takes real dimension of the danger to which they are exposed.

The Madero manage to leave their differences aside and work side by side following the traces that the murdered grandfather left in his notebook. Ugarte, close to the truth, will face Basualdo.

After the murder of Ugarte, Luis and Camila are forced to seclude themselves. The deaths continue. Ignacio will sit face to face to negotiate with Basualdo, the enemy. All that remains is to decipher a sheet.

The government joins the investigation. Basualdo, cornered, becomes more dangerous and wants the Maderos to decipher the last sheet of "The Operations Plan" and thereby make it disappear.

The life of Faletti depends on the skill of the Madero to manage to unravel the mystery of the last page of the manuscript. Basualdo, cornered, will play his last card to get the writing.