The CBI team investigates the death of the senator's intern, Kristen Marley. Suicide is ruled out by Jane when he notices that her one shoe is missing.
Through the grapevine the team hears that senator Melinda Batson's husband, Elliot, was having an affair with the victim. But Jane learns that Kristen was acutally having an affair with Melinda's father, Walter Crew.
Kristen's missing shoe is found in her step-brother's car by Cho and Rigsby. On the night of the murder he was released from a carjacking arrest. The step-brother, Harlan, claims that he was set up and Jane believes him, stating that he will arrest the real killer within 12 hours. He finds a bug in one of the lights and traces it back to a private investigator, Art Cavalleri who was hired by Walter Crew who posed as a CBI janitor.
Jane and Lisbon tracks Art down but he is killed in the car chase. Elliot, Melinda and Walter is brought in for questioning by Lisbon. Elliot admits to his arranged marriage and reveals that Kristen and Melinda were lovers but that Kristin chose Walter in the end.
Melinda killed Kristen and her father helped her to cover it up.
Jane extends an offer of peace to Bosco and his team. He bugs Bosco's office and so learns more about the progress on the Red John investigation.