In the second installment of the epic fantasy trilogy, the divided fellowship faces new dangers on their quest to destroy the One Ring. Frodo Baggins and Samwise Gamgee continue their perilous journey towards Mordor to defeat the dark lord Sauron. They are joined by Gollum, a creature torn between his lust for the One Ring and the remnants of his former self, providing them a guide with uncertain allegiance. As Frodo and Sam venture deeper into enemy territory, they must rely on each other more than ever, but Gollum’s presence and the Ring’s influence test the boundaries of their friendship and resolve.

Meanwhile, Aragorn, Legolas, and Gimli pursue the abducted Merry and Pippin through the lands of Rohan, a kingdom under threat from both Saruman’s emerging army and the indecision of its king. The trio's search leads them into alliances with the proud Rohirrim and their conflicted king, whose mind is clouded by Saruman’s sorcery. As the forces of darkness converge, they must rally the people of Rohan against the imminent onslaught, preparing to make a stand at the fortress of Helm's Deep. Simultaneously, the once peaceful lands face a new onslaught of evil, and the companions learn that the success of the ring-bearer’s quest will profoundly influence the outcome of these greater battles.