Fernando and César said goodbye at an airport in the United States in 2019. Since then, they have not seen each other again. One day before the declaration of the state of alarm in Spain, foreseeing the exceptional nature of what was to come, Fernando feels the urgency of sending a filmed letter to César. The two friends thus begin an intense correspondence that they will maintain until the start of the de-escalation. That diary in images marked by the uncertainty is called 'Interregnum'.Interregnum is a period of discontinuity of a social order. It is a time in parentheses in which the usual functions are interrupted, normality becomes strange. Telepreachers conspire against the apocalypse, or perhaps invoke it. New species appear in everyday life. Deep changes are sensed. In the interregnum, time stretches and stands still without a glimpse of how the exit will be.