Proteus does not want to go because he will have to leave behind Julia, with whom he is smitten.

One in Milan, Valentine falls in love with Silvia, the Duke's daughter but Silvia is promised to Thurio.

Silvia although promised to a very wealthy Thurio returns favor with Valentine and so Silvia and Valentine run off and elope.

The further the play goes along, the messier it gets.

Valentine confides his secret plan to Proteus, who, most unfortunately is also now quite taken with Silvia and now to get Valentine out of the way, Proteus tells the Duke on Valentine. The Duke banishes Valentine and Silvia is placed under lock and key, and Proteus wins much favor with the Duke and thus becomes a confidant of the Duke in matters concerning Silvia. Banished and alone, Valentine eventually joins a group of outlaws and becomes their leader. Meanwhile, Julia has come to Milan in search of Proteus under the disguise of a page while Proteus is trying to win Silvia who is still longing for Valentine and wants nothing to do with Proteus or Thurio.

In a twist of fate, Julia, still disguised as a page begins work for Proteus and becomes the intermediary between himself and Silvia until Silvia escapes to Milan in hopes of finding her Valentine.

Lucky for Silvia, she is captured by Valentine's outlaws but upon hearing of his daughter's escape, the Duke along with Thurio and Proteus go in search of her.

Unlucky for Silvia, Proteus finds her before the outlaws have gotten her to her Valentine but then, Valentine happens upon Silvia and Proteus just as Proteus is about to claim his love to Silvia.

Valentine and Proteus come to terms with each other and as a gesture of peace, Valentine offers Silvia to Proteus. Julia still disguised as Proteus's page then faints and much to his shame, Proteus recognizes his Julia whereupon the Duke with Thurio arrives at the scene. Valentine challenges Thurio for Silvia and Thurio walks away.

In the end, everyone lives happily everafter and Valentine and Silvia are together with the Duke's approval and Julia and Proteus also get back together and all of Valentine's outlaws are pardoned by the Duke.