More than 30 million viewers stopped by Wisteria Lane on Sunday night as ABC’s smash rookie drama “Desperate Housewives” unraveled some knots and then tied up a few new ones with its season finale.

A sexy, sudsy slice of suburbia, “Housewives” quickly became a water-cooler show last fall and has exploded into one of the biggest pop-culture phenomena in years, playing a huge role in ABC’s renaissance season.

Its hourlong finale racked up the best young-adult rating for a drama episode on any net in three years and the best for an Alphabet hour in more than 10 years.

Along with powerful perfs by two other season-enders — “Grey’s Anatomy” and “Extreme Makeover: Home Edition” — ABC dominated the final Sunday of the season in all categories, including its best demo scores on the night with series in 7½ years.

Based on preliminary nationals from Nielsen, “Desperate Housewives” (9-10:02 p.m.) is projected to come in with a 13.5 rating/31 share in adults 18-49 and 30.8 million viewers overall. This is about 30% above its season average and the second highest 18-49 score for any series telecast this season, behind only the season preem of Fox’s “American Idol” in January (14.0/33).

In overall total viewers, only the “Idol” premiere, a November episode of “CSI” and the season finale of “Everybody Loves Raymond” figure to rank higher this season.

“Housewives” delivered the best 18-49 score for any drama on any net since an episode of NBC’s “ER” in May 2002, and the best for an ABC drama since “NYPD Blue” in December 1994. It also becomes TV’s highest-rated first-year drama finale since “ER” in 1995.

Leading out of “Housewives” was a very strong season finale for hot medical drama “Grey’s Anatomy” (roughly 9.6/25 in 18-49, 21.9 million), which dominated its slot with series highs. Also, “Extreme Makeover: Home Edition” rolled at 8 (prelim 6.9/19 in 18-49, 17.3 million), posting its best scores since March.

Overall, ABC’s 8.5 rating in 18-49 marks its best on a Sunday (excluding the Super Bowl and Academy Awards) since November 1997.

Elsewhere, Fox did reasonably well with the network preem of “Star Wars: Episode II — Attack of the Clones” (prelim 3.6/10 in 18-49, 8.5 million) while three crime dramas left CBS third in demos.

NBC was led by “The Contender” (prelim 2.6/7 in 18-49, 5.9 million). Net likely confused viewers by inexplicably switching the slots of dramas “Law & Order: CI” and “Crossing Jordan,” both of which bombed.