may sweeps 2012 May TV: A 'Big Bang Theory' wedding, 'Glee' goes to prom and 5 more sweeps must seesThe spring rerun doldrums are over. Cue up the crossovers, the weddings, the stunt casting and the shocking twists, because it’s sweeps time.

Starting Thursday night (April 26), your favorite shows will almost certainly be in original episodes until they reach their season finales, and they’ll be doing everything possible to grab your attention between now and then. There’s a business reason for all that — ratings during sweeps periods help set the ad rates for local stations — but the upshot for us is that it makes for a lot of fun viewing (and potentially some crowded DVRs).

Here are seven things to look out for as we steamroll toward the end of the 2011-12 season.

Weddings galore: CBS is going nuts for nuptials in the coming weeks. “NCIS,” “The Big Bang Theory,” “How I Met Your Mother” — in which we finally get to see Barney’s (Neil Patrick Harris) bride — “Mike & Molly” and even “Criminal Minds” will feature wedding storylines between May 8 and May 16.

Sexy time! Amid the high stress of preparing for the boards, Kepner (Sarah Drew) and Avery (Jesse Williams) get hot and heavy on Thursday’s “Grey’s Anatomy.” Look out for more trysting on “90210,” “New Girl” and “Smash,” at least.

Crossover minus one: Is “Hawaii Five-0” really “Hawaii Five-0” without McGarrett? We’ll see on April 30 when the show begins a crossover with “NCIS: Los Angeles” minus star Alex O’Loughlin, who missed the episode while going through rehab. The story — about the hunt for a criminal threatening to release a lethal virus — concludes on “NCIS: LA” the following night.

A prom here, a prom there: Both “The Secret Circle” and “Glee” will do that staple of high-school shows, the prom episode. The “Prom” episode of “The Secret Circle” on May 3 finds some of the young witches in a life-and-death situation, while “Glee’s” “Prom-asaurus” episode on May 8 features a heated campaign for king and queen and an alt-prom thrown by some of the outcasts.

Blast from the past: The May 9 episode of “Revenge” takes us back to 2002, when Emily/Amanda starts reading her father’s journals at Nolan’s urging — and starts to formulate her plan to take the Graysons down. We’re intrigued as all get out (and kind of tickled by the idea of Emily VanCamp playing a teenager again, since 2002 was when “Everwood” premiered).

Summer starts early: Just as “summer” at the movies now starts the first weekend in May, a couple of flagship summer TV series are premiering before the official end of the season. ABC’s “The Bachelorette” and NBC’s “America’s Got Talent” will both start their seasons on Monday, May 14.

Saying goodbye: Two of the longest-running shows from the stellar rookie class of 2004-05 — for our money, the best season for new series in recent memory — will end eight-season sagas in May. “Desperate Housewives” bows out with a two-hour finale Sunday, May 13 on ABC, and “House” diagnoses its last case Monday, May 21 on FOX.

Posted by:Rick Porter