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...

Upon returning to Crete, Kiritsis finds a dying Maria. Once again, just as he once did in Spinalonga, he has to save her. But he fears that this time he may not succeed. Meanwhile, Rinio professes her love for Manolis for the first time, in hopes her love will be requited. But is Manolis ready to love a woman and change his single ways? Meanwhile, Vangelis professes his love for Katerina and suggests she comes away with him, far from Crete, prison and her husband. Anastasis continues in vain to search for Filippos, the boy he once loved, until he suddenly has an unexpected visit. Andreas is intrigued by a mysterious enigmatic prisoner who enters the prison.