While investigating the homicide of an overzealous journalism student, Jane is not happy when a former colleague returns to BPD as the new lieutenant of the drug unit. But the murder she’s investigating soon forces her to deal with him – and the event wrecked their relationship. Meanwhile, an alarming tip from Cailin causes Maura to investigate Hope.
An investigative journalism student is found dead on the beach. The cause of death is determined as a drowning, but her lungs contain freshwater and not the ocean's saltwater. The student had been investigating a drug ring at her university. Jane must grudgingly work with a former colleague, who is now a new drug-unit lieutenant, in order to solve the case. Elsewhere, Maura learns that her mother Hope received a sizable donation to open her charity clinic. The donor was Paddy Doyle. He is asked to give his statement about how he got the money, so the FBI will leave Hope alone, but he refuses.
- Angie Harmon as Detective Jane Rizzoli
- Sasha Alexander as Dr. Maura Isles
- Jordan Bridges as Officer Frankie Rizzoli, Jr.
- Lee Thompson Young as Detective Barry Frost
- Bruce McGill as Detective Vince Korsak
- Lorraine Bracco as Angela Rizzoli
- Brian Goodman as Sean Cavanaugh
- Amaury Nolasco as Rafael Martinez
- Sharon Lawrence as Hope Martin
- Emilee Wallace as Cailin Martin
- Jon Curry as Bob Thatcher
- Tina Huang as Susie Chang
- Brooklyn McLinn as Tyrell Feeney
- Emily Davenport as Brenda Thomas
- Tanya Chisholm as Rachel Cooper
- John Doman as Patrick "Paddy" Doyle
- Shenita Moore as Shaundra Lewis
- Chelsea Rendon as Yolanda Rojas
- Alyssa McBride as Emily (Brenda's Roommate)
- Detective Vince Korsak comments that Psi Beta Tau sorority girls, just like in his day, were "foxy, smart." Rizzoli points out that Korsak never attended college, and he replies "I went to a lot of toga parties." The actor who plays Korsak is Bruce McGill, who played Daniel Simpson Day ("D-Day") in Animal House (1978), which had one of the most famous toga party movie-scenes of all time.