All season long, Cat has been searching for the truth about her father's murder. This week, she finally got it - but not without a price. Read more about...The Case of the Capellas' ComebackCat's obsession with the crime family leads her to stake out the apartment building of a man named Mario, who an anonymous tip claims is running a wholesale drug business for the Capellas. Leo accompanies her, but he is more focused on the 2-on-2 basketball tournament he's playing in. The winners receive $10,000 and Leo plans to use the money to fly Nico and his ex-wife to New York.A motorcycle messenger arrives to the building then to make a delivery. Nothing seems out of the ordinary - until another messenger pulls up, shoots the first one and takes off with the package. Cat calls for backup and she and Leo give chase. But the shooter gets away after driving into a park.A search of Mario's apartment turns up paraphernalia for heroin use, but no Mario, so Cat is forced to wait on his return. At the precinct, Capt. Baker surprisingly reinstates Cat's driver's license and thereby terminates her partnership with Leo. The pair parts after an extended handhold and Leo invites Cat to watch him play in the tournament, but we're sure this isn't the last we've seen of the dynamic duo.Cat next questions the messenger service's dispatcher. She says the drivers work freelance and she rarely meets them nor does she know what the packages contain. The only information she can provide is a list of how many deliveries have been made to Mario's address. Meanwhile, during basketball practice, Leo spies his teammate Roger receiving an envelope full of cash. Leo confronts him, but Roger plays it off as rent money from his mother.Back at the precinct, Cat is about to take her new car for a spin when she sees a truck drive past and knock her side view mirror off. It's the second time that day her car has been damaged after a bird defecated on it earlier. When she and Esposito finally get to Mario's apartment – the building's super alerted them to his return – Mario has fled out the fire escape. Cat chases after him on foot, but it's Leo who stops Mario when he opens his cab door into Mario's path. Leo explains that he realized his life is boring without police work and so he followed Cat.Under questioning, Mario denies being a drug dealer and says he was receiving only a small amount of heroin to help his girlfriend cope with withdrawal. Cat is not entirely convinced and her suspicions are proved correct when shortly after, one of the Capellas' lawyers bails Mario out of jail.When Leo's team advances to the finals, Cat is there to see him do it. Unfortunately, so is Luke Capella, who watches the game from the backseat of his limo. Afterward, Cat asks Leo to give her a lift as she drops off her car at an auto-body shop. The shop is run by Cat's uncle A.J., who reminisces about the last time he saw Cat's father during her visit. Cat is surprised to learn A.J. had seen her dad with Ned Lipinski, a cop later found to be working for the Capellas.As she and Leo leave the shop, Cat receives a phone call alerting her that Mario has been found dead. He was shot twice in the back of the head, Capella-style. Leo surmises that the Capellas probably bailed him out of jail and then killed him to keep him from revealing anything to the cops. To find out more, Cat and Leo visit another messenger who had delivered to Mario. He says he received the package at the dock, where it was delivered by shady Italians who arrived via boat. The package was always a briefcase and it was always Mario that it was delivered to.On the way to the precinct, Leo gets a call from Roger who says they have to lose the finals if they want to live. Further explaining in person, Roger says the Capellas will pay them $20,000 to do so, but Leo refuses to participate. Instead, Leo names Cat as his alternate and she agrees to take Roger's place. Lucky for Leo, it turns out Cat was a basketball star in high school.Following Mario's death, Cat and Leo re-search his apartment and find receipts for all of the deliveries stashed in his freezer, along with a note written in Italian. To translate it, Cat seeks help from an unlikely source - Giada. Giada reads Mario's letter in English, which reveals he knew someone had become aware of what was in the briefcases. He also identifies his girlfriend, Angie. Cat, Leo and Giada find Angie living one apartment above Mario.Angie is deep into withdrawal as she answers Cat's questions. She reveals Mario accepted the job as a middleman for the Capellas in order to fund Angie's drug habit. He collected $100,000 every Friday and Monday on their behalf. It was money made in Atlantic City from prostitution, drugs and other illegal activities, hence why it arrived by boat.The investigation is put on hold when Cat is called into Baker's office, where Gregg and Esposito are also waiting for her. Baker reveals that Cat's father was a dirty cop. Gregg further adds that he was working for the Capellas and that Luke Capella is believed to have killed him. A shocked Cat punches Gregg after learning the details and flees the precinct.Returning to the case, Cat waits in her car at the dock until a messenger arrives to pick up the latest Capella package. However, a second messenger soon pulls up and steals the motorcycle carrying the briefcase. Cat and Leo both chase after the motorcyclist, cornering them in a parking lot and forcing the messenger to crash into Cat's car. They remove the motorcycle helmet to find the culprit is the messenger service's dispatcher. She attempts to bribe Cat and Leo if they'll let her escape to Rio like she planned, but the pair is distracted by seeing Cat's new vehicle erupt in flames.There's little time to mourn the car, though, because Cat and Leo have a game to get to. As they enter the court, Cat is stopped by Luke Capella, again watching the game from his limo. She threatens to take him down; he calls her dad the best cop the family ever had on the payroll.Luke's comments successfully unnerve Cat, who plays poorly for the first half of the game. Leo pulls her aside for a quick chat and Cat tells him the truth about her dad. Leo's words of encouragement put Cat at ease and she ends up sinking the game's winning basket, ensuring Leo gets the prize money. But amid the celebration, Cat sneaks away and returns home to a collage she's made about her dad's murder. While staring at a photo of Luke Capella, she says, "You're a dead man."Will learning the truth about her father's past unravel Cat? Can Leo, Gregg, Baker and Esposito stop her before she goes to war with the Capellas? We'll be holding our breath during what is sure to be an explosive season finale next week.