In a world where superheroes and villains intertwine, Eddie Brock has found a strange peace with his symbiotic partner, Venom. After the traumatic experiences they went through together, Eddie tries to reintegrate into his life as a journalist while dealing with the consequences of his somewhat toxic relationship with Venom. However, tranquility is shattered when Cletus Kasady, a death-row serial killer craving revenge, appears.
Cletus, portrayed by the charismatic Woody Harrelson, is possessed by his own symbiote, transforming him into one of the most dangerous villains of all time: Carnage. His thirst for blood and chaos tests both Eddie and his unusual partner. As the two adversaries clash in a battle that will combine frantic action with moments of dark comedy, Eddie finds himself caught in a deadly game where the stakes have never been higher.
As Venom and Kasady fight for dominance, Eddie must decide how far he is willing to go to protect his loved ones and confront his own demons. The film explores not only the duality of these characters but also the complexities of friendship and the true nature of the monster that resides in all of us. Caught between two worlds, Eddie must discover what it really means to be a hero, or at least, a version of it.