American Idol (8pm, Fox) - It's time for the judges to lock them doors and turn them lights down low -- and finally unveil the Top 24 semifinalists, which will consist of 12 males and 12 females. Will Garner's country-crooning Scotty McCreery (left) be in that group?
Big Bang Theory (8pm, CBS) - Sheldon learns he's not the epicenter of the group and decides to find new friends.
Grey's Anatomy (9pm, ABC) - Meredith discovers that her fertility treatments are causing her to lose her visioni, and Mark tells Callie and Arizona that he plans to be an active dad when the baby comes.
Royal Pains (9pm, USA) - In the Season 2 finale, Hank tries to get to the root of what's ailing a patient he thinks has been misdiagnosed. Elsewhere, Divya and Raj take dance lessons for their upcoming wedding, but things don't go as planned.
Parks & Recreation (9:30pm, NBC) - Ron and Leslie head to Indianapolis, where they'll be recognized for their work on the upcoming Harvest Festival. Back in Pawnee, Tom hosts a launch party for a local cologne maker, and Andy and April find ways to have fun without spending money.
30 Rock (10pm, NBC) - Liz hires a new female writer after a blog declares "TGS" misogynistic. Meanwhile, Jack plots his takeover of Kabletown by zeroing in on his main competition -- the CEO's granddaughter.
Archer (10pm, FX) - When members of Woodhouse's WWI Royal Flying Corps squadron (the "Double Deuce") start dying mysteriously, he naturally suspects foul play. So does Archer, who' sin for some multitasking: tracking down the killer while babysitting his young son Seamus.