Reality TV beauty Kay Cappucchio (guest star Hilarie Burton) is in the house at the Sunfair Kennel Dog Show. She's promoting her new "Guilty Pleasures" perfume alongside her manager/boyfriend Reggie Starr (guest star Justin Hartley). Out on the floor, famed dog trainer Francisco Pilar makes his choice for Best in Show. After the competition, Francisco is strangled to death with a leash. Now Castle and Beckett must collar a cold-blooded killer.
Kay Cappucchio was caught on camera leaving Francisco's dressing room around the time of the murder. You just can't escape the watchful eyes of fans and paparazzi. This is something Castle learns when eager shutterbugs mistake him for Jason Bateman. Beckett laughs pretty darn hard at this one.
Kay Cappucchio had hired Francisco to do some behavior training with her dog, Lolita. She says the victim was already dead when she stopped by his room. Francisco was reportedly paranoid that Kay was working with someone. Rumors are that the guy may have been taking bribes to fix dog shows. That could explain the string of cash deposits he'd been making, as well the many "underdog" winners he'd been selecting lately.
The victim's only family is his loyal pooch, Royal, who is seen pawing at the floor after the murder. Castle convinces Beckett to keep the dog at the precinct as a temporary mascot. Ryan loses at roshambo (aka Rock-Paper-Scissors) to fetch some dog food while Castle and Beckett question Francisco's therapist. As it turns out, Dr. Patty Barker is actually Royal's therapist. They should have known she was a dog shrink with a name like "Barker."
Electronic sweepers found in Francisco's place indicate the guy was worried he was being bugged. Beckett and Esposito discover that Francisco visited a warehouse filled with dogs. A man who worked for him says Francisco was breeding a new kind of designer dog: the Pilar Retriever. He says the cash deposits were from investors who knew about his plan. He also suggests Kay Cappucchio was trying to steal his secrets.
Francisco's bug sweeper goes off when Kay is brought in for questioning. As it turns out, her dog's collar has been fitted with a hidden camera. Esposito offers to sift through photos of Kay to look for clues in the case. We're not sure what's happening with Lanie, but Javier seems to have mild case of puppy love for Kay Cappucchio. He realizes she's a little bit more than what people see on TV.
Speaking of puppy love, Castle gives Beckett tips on how to care for Royal. He shows her how he likes to be rubbed by making circles with his thumb on the back of her hand. It starts out as a perfectly innocent moment, but then something happens. The look the two of them share lets us know this hand-holding exercise stirred some feelings inside. Moments later, Beckett is being showered with kisses...from Royal the dog after Castle has left the building.
The team tracks down the slimy photographer who planted the collar-cam on Kay Cappucchio's dog. Paparazzi stalker dude says he heard Francisco talking about possible drug deals. The man Beckett met at the warehouse confirms this. He's a U.S. Customs agent. He says Francisco was training drug-sniffing dogs to paw at the ground to indicate contraband. The program was causing the Vasquez drug cartel to lose a fortune.
Royal paws at the ground when he sniffs Kay Cappucchio's perfume on Beckett. The main ingredient comes from poppy flower. Castle suggests that Royal was pawing at the yet-to-be-released perfume scent at the crime scene to help identify the killer. Kay Cappucchio has connections to the Vasquez cartel, but Esposito refuses to believe she's a murderer. Castle is able to prove him right.
Kay's agent/boyfriend, Reggie Starr, is the one who introduced her to the Vasquez family. He also got doused with some perfume at the dog show just before the murder. When Reggie bolts, Royal gives chase until Esposito takes the killer down. Case closed.
Castle and Beckett agree that splitting time with Royal is not the way to go. No problem. The orphan pooch opts to live with Kay Cappucchio, who says she may call on Esposito someday. Castle admits that Royal would be better off hanging with Kay's dog, Lolita. The two of them really seem to enjoy each other. We agree. These two really do enjoy each other. And we're not talking about the dogs.