(rated PG, 90mins.)   The Mayflower Kennel Club Dog Show provides the backdrop for this ensemble comedy of dysfunctional humans that succeeds on its improv/ documentary style, certain to leave you rolling over like a dog in the theatre aisles. First there’s the Karma Sutra loving couple with a serious case of OCD who believes their dog “Beatrice” needs therapy after watching them have sex. Then there’s the man with literally two left feet who is married to the town tramp. Their terrier, ‘Winky” brings them closer to marital bliss. In addition, there’s the man from Carolina with the blood hound named “Hubert” who gives new meaning to the fact that pets resemble their owners. And, love the gay couple from SoHo with their tiny Shih Tzu named “Miss Agnes” who packs a wardrobe of six kimonos for 48 hours in Philadelphia. But it’s the plastic-surgery-laden-Ivana-Trump-gold-digging-look-alike from Philly who’s married to a catatonic 95 year old man who steals the movie with her lesbian dog trainer lover, with their champion poodle, “Rhapsody In White”. The story reunites director Christopher Guest “Waiting for Guffman” with his co-stars Fred Willard, Bob Bababan, Patrick Cranshaw, Lewis Arquette and Ed Begley Jr. No independent film would be a hit however without the indie queen herself, Parker Posey as the owner of Beatrice the Weimaraner. The story leaves you with a rationalization that dog lovers are their own mentally obsessed breed and that they, not the dogs, are in need of obedience school. Ruf!