Best in Show is presented as a documentary of five dogs and their owners destined to show in the Mayflower Kennel Club Dog Show, held in Philadelphia. The documentary jumps between the owners as they prepare to leave for the show, arriving at the hotel, and preparing backstage before their dog takes the show. The owners and their dogs include:Gerry and Cookie Fleck (Eugene Levy, Catherine O'Hara), with their Norwich Terrier Winky. They are a middle-class couple from Florida who run into monetary problems and are forced to sleep in the hotel's storage room when they finally arrive. Throughout the film, they encounter men that Cookie had slept with during her youth.Meg and Hamilton Swan (Parker Posey, Michael Hitchcock), with their Weimaraner Beatrice. An upper-class, stereotypical yuppie couple, they take great care in Beatrice (although really just confusing and aggravating her with their neurotic behavior), going as far as taking her to a therapist after she saw Meg and Hamilton have sex. At the show, the Swans believe that Beatrice will become unnerved without her favorite toy, the "Busy Bee", and frantically search for a replacement for it before the show.Harlan Pepper (Christopher Guest) and his Bloodhound Hubert. The Peppers have raised bloodhounds for generations, and Harlen continues the tradition, though he has aspirations of becoming a ventriloquist.Sherri Ann (Jennifer Coolidge) and Leslie Ward (Patrick Cranshaw) Cabot with their standard poodle Rhapsody in White (a.k.a. Butch), a two-time winner of the show in the past. Sherri Ann is a luscious big-breasted blonde, having the elderly Leslie as her sugar daddy. She is primarily worried about giving Rhapsody a makeover; however, trainer Christy Cummings (Jane Lynch) makes sure the dog is ready for the show, while Leslie stays utterly oblivious and apathetic. Over the course of the film, the fake couplehood between Sherri Ann and Leslie crumples while Sherri Ann's romantic involvement with Christy becomes apparent.Scott Donlan (John Michael Higgins) and Stefan Vanderhoof (Michael McKean) and their Shih Tzu. The gay couple takes great pride in their dog, and are confident that she will win the competition. They gossip about the other participants throughout the film.The owners and their dogs all arrive in time for the show, which is hosted by Trevor Beckwith (Jim Piddock), and "color" commentator Buck Laughlin (Fred Willard). During the first round, Beatrice is disqualified when Hamilton cannot control her, but the other four dogs advance to the final round. Just before the finals, Cookie stumbles and insists that Gerry take over for her. Though the audience is initially awed by seeing Gerry's "two left feet" (the result of a birth defect), ultimately Winky takes Best in Show.Afterwards, the film explores what each character is doing after the competition. Gerry and Cookie returned home to Florida and were overcome with attention after the victory. They go on to record, in amusingly bad style, songs about dogs. Sherri Ann and Christy have entered into a partnership and publish a magazine for lesbian dog owners called Modern Bitch. Harlan fulfills his dreams and becomes a ventriloquist, entertaining sparse crowds with a honky tonk song and dance number. Hamilton and Meg Swan have found a new dog, one that enjoys watching them make love, and are sure it will be a winner. Stefan and Scott are in the process of designing a calendar featuring Shih Tzu dogs appearing in scenes, with appropriate costume, from famous classic films, such as Gone with the Wind and Casablanca.