Brenda and Donna attend an animal rights rally, and are crestfallen when the university refuses to suspend animal testing. After Rocky dies of cancer, Brenda becomes involved with a small group of radicals. She serves as lookout when the group breaks into the university research building, and tries in vain to save Andrea's lab (which does not harm animals in its testing). Brenda is arrested. Kelly and Brandon are furious when Dylan refuses to fund Lucinda's film. He finally tells Kelly that Lucinda came on to him. Brandon breaks up with Lucinda, and Kelly confesses her kiss with Brandon. Dylan races over to the Walsh house to fight Brandon, but the tension is defused when he accidentally punches Steve.

Brenda calls Dylan from jail in the hopes of keeping her arrest a secret, but he is forced to tell her parents. Brenda's friends avoid her out of fear of being accessories after the fact, and Kelly acts especially bitchy because she is tired of Dylan coming to Brenda's rescue. Brenda faces felony charges, as her crime was a federal offense. An FBI agent who had gone undercover with the activists offers her immunity in exchange for her testimony. Kelly apologizes for shunning Brenda. Andrea gives Donna a healthy puppy (Rocky II) to take her mind off Rocky's death. Steve and his overbearing father, Rush, take on a baseball star and his dad in a father/son golf tournament. Steve catches his father cheating and forces him to complete the game honestly. Lucinda receives a grant for her movie and leaves the university. Josh threatens to expose Brandon's affair with Lucinda unless he endorses his campaign for student president. Brandon calls his bluff, and Josh eventually has second thoughts.