On Miami Vice one cop wears no socks and lives on a boat with an alligator named Elvis. The other wears designer suits and is a fish-out-of-water from the Bronx. They are Sonny Crockett (Don Johnson) and Ricardo Tubbs (Philip Michael Thomas), Miami undercover vice detectives who bust drug dealers, pimps, and other sleazeballs, while operating fast cars, faster boats, and very big guns. When it debuted 20 years ago, the show made a pop-cultural impact with its flashy/gritty visuals, cinematic pacing, pastel fashion statements, and action sequences scored to chart-topping hits. It no longer seems as slickly stylish as it used to, but it's still an entertaining artifact of the decade it helped define. EXTRAS A conventional menu of behind-the-scenes featurettes extol the style, music, and ''vibe'' of the show. But perhaps the most telling tidbit recalls an anecdote crediting the late NBC honcho Brandon Tartikoff with the two words that supposedly, inspired the series: MTV cops.