Best friends Valentine and Proteus say goodbye to one another on a road in Verona. Valentine is wandering out to see the world, while Proteus remains home in Verona, tied by his adoration for Julia. After Valentine withdraws, his worker, Speed, enters. Proteus asks whether Speed conveyed a letter to Julia, to which Speed answers that he has. Julia, in the meantime, asks her cleaning specialist, Lucetta, which man she should pursue, and Lucetta recommends Proteus. Lucetta concedes that she has a letter for Julia from Proteus. After much quarreling, Julia tears up the letter, just to lament this demonstration a moment later.
Antonio chooses to send Proteus, his son, to the Duke's court in Milan, a choice with which neither Proteus nor Julia is especially cheerful. They trade rings and promise to continue adoring each other. In the meantime, Valentine has begun to pursue the Duke's feisty daughter, Silvia. When Proteus touches base at court, he too experiences passionate feelings for Silvia, and pledges to do anything he can to win her over from Valentine. When Valentine admits that he and Silvia intend to abscond, Proteus informs the Duke of their plans, picking up support for himself and initiating Valentine's expulsion from court. Back in Verona, Julia has brought forth an arrangement to camouflage herself as a man so she can travel to Milan to be reunited with Proteus. After checking in at court, she witnesses Proteus and Thurio charming Silvia.
The exiled Valentine, while making a trip to Mantua, is intercepted by a gathering of bandits. The fugitives, every one of whom are exiled respectable men too, request that Valentine become their ruler. Since they threaten to murder him in the event that he rejects their request, Valentine complies. Silvia and Julia, who is veiled as the page Sebastian, meet when Julia conveys the ring Proteus had offered her to Silvia for the benefit of Proteus. Julia does not reveal her true identity. Silvia approaches her companion Sir Eglamour to help her escape her dad's abusive will (he needs her to wed Thurio) and to find Valentine. While going through the woodland, she and Eglamour are passed by a band of bandits. Eglamour flees, leaving Silvia to battle for herself against the bandits. At this point, the Duke, Proteus, and Thurio, with Sebastian/Julia close by, attempt to find Silvia.
Proteus wrests Silvia from the fugitives. Valentine watches the commotion while concealed. Proteus requests that Silvia give him some indication of her support for liberating her, yet she will not. He tries to assault her, but Valentine hops out and stops him. Proteus quickly apologizes, and Valentine offers to give him Silvia as a token of their fellowship. Sebastian reveals his true identity as Julia. Proteus concludes that he truly cherishes Julia more than he does Silvia, and decides to wed Julia instead. The Duke understands that Thurio is a fool and says that Valentine is far nobler and can wed Silvia. Valentine requests forgiveness for the bandits, and recommends that his marriage to Silvia and Proteus's marriage to Julia should occur around the same time.
