Pani unfolds through various natives of thrissur city, their experiences and chance encounters. It primarily revolves around Giri and Gauri, who live a fulfilling, content and a happy married life. However, their tranquil existence is unexpectedly disrupted when two youngsters with a criminal inclination intentionally invade their beautiful world. The story then explores the trials and tribulations that befall the 'Mangalath' family in which they belong. When Gouri gets devastated by the nightmarish incident, Giri bursts out to avenge the ruthless culprits. As Giri lives a reformed life from being a gangster to a family man, he decides to revive his old 'Thrissur' gang along with his mobster friend Davi and his squad. They all become a part of this vendetta, making a retaliation. 'Pani' weaves a gripping chain of events that evolves through love, vengeance, intense emotions and suspense.