DESPERATE HOUSEWIVES - "Down the Block There's a Riot" - Paul's nefarious plan for Wisteria Lane is put into full effect, Juanita discovers Gaby's secret, Bree invites Keith to move in with her, and Tom is confronted about his past indiscretion with Renee, on "Desperate Housewives," SUNDAY, DECEMBER 12 (9:00-10:01 p.m., ET) on the ABC Television Network. (ABC/CRAIG SJODIN) TUC WATKINS, KEVIN RAHM, FELICITY HUFFMAN