After taking last Friday off for the swan song of veteran Smallville, CW’s Supernatural returned last night for its own season closer. The finale drew 2.1 million viewers and a 0.8/3 in adults 18-49, down 20% in the demo from the show’s last original. With CBS’ established Friday dramas CSI: NY and Blue Bloods in repeat/replaced by 48 Hours Mystery, respectively, after ending their seasons last week, Flashpoint (0.9/3) at 8 PM dropped 31% from last week. Fox (average of 1.5/6) won the night in 18-49 with a new Kitchen Nightmares (1.6/6), the highest-rated program of the night, followed by a repeat of the unscripted series (1.4/5). ABC (1.3/4) was second with a Shark Tank rerun and newsmagazines, followed by NBC, which aired Friday Night Lights (0.9/3, up a tenth) and Dateline.