1) “Snowfall” season-finale, 10 p.m., FX, rerunning at 11. The last two weeks have delivered fierce jolts. First, Franklin killed Andre, the honest neighborhood cop. Then Melody – Andre’s daughter, Franklin’s former girlfriend – shot Franklin three times, leaving him for dead. Will he survive? Where does the show go from here? Viewers will have to wait until the final minutes to find out. Much of this hour – frustrating, yet fascinating – is a “what if” detour. Then key questions are answered.
2) “BH90210” finale, 9 p.m., Fox. It was a clever idea, anyway: Fight the end-of-summer blahs with a six-episode quickie that has “Beverly Hills, 90210” stars playing fictional versions of themselves. Alas, the execution has been so-so and the big opening ratings have fallen by half. Tonight, people nervously await word from the network. Meanwhile, there are key marital moments for Jason Priestley, Tori Spelling, Brian Austin Green … and Gabrielle Carteris, who introduces her girlfriend to her husband.
3) “America’s Got Talent,” 8 p.m., NBC. By the end of this hour, “Talent” will have its 10 finalists. It chose half of them last week; the other half will be chosen from the 11 acts that performed Tuesday. That sets up the finals, next Monday and Tuesday.
4) More reality. At 8 p.m., it’s “Big Brother” on CBS and “MasterChef” — the final four in London – on Fox. And at 9:01, “Songland” concludes. Songwriters pitch to Ryan Tedder of OneRepublic.
5) Sept. 11 films, all day, cable. On the 18th anniversary of the Sept. 11 attacks, here are documentaries. The History Channel has a 25-hour marathon, from 7 a.m. today to 8 a.m. Thursday. National Geographic goes from 9 a.m. ET today to 2 a.m. ET Thursday; Smithsonian has films from 3-5 and 6-7 p.m. And expect more coverage on news channels and the network newscasts.