The narrative thread of the series "One August Night" unfolds from the murder of Anna Petraki (Evgenia Dimitropoulou) by her husband Andreas Vandoulakis (Yannis Stankoglou), one night in August, six years ago, when the latter learns that she had a lover, his cousin Manolis Vandoulakis (Yorgos Karamihos).
The main role in the series is played by Anna's sister, Maria Petraki (Youlika Skafida), who tries to continue her life, keeping well-hidden secrets that must not come to the surface...

The last days of Rinio make Manolis finally come face to face with his feelings and needs. He now accepts that he needs love and family. So, when Rinio passes away, Manolis thinks for the first time about taking on the role of father to little Christina. He is unaware, however, of the existence of the letter addressed to him - Andreas' mysterious letter. At the same time, Agathi thinks, for the first time, of leaving Piraeus behind forever and going somewhere far away. Andreas, placed in solitary confinement to escape from Stathakakis and Chronis, gets close to the shaman. Maria unexpectedly finds a person from the past in front of her: the prison officer who had abused her.