"How I Met Your Mother," "Two and a Half Men," "The Big Bang Theory," "CSI: Miami" (starting at 7 p.m., WBBM-Channel 2): Season premieres.

"Heroes" (7 p.m., WMAQ-Channel 5): In the fifth season premiere, Claire adjusts to college life. How time flies.

"House" (7 p.m., WFLD-Channel 32): The crotchety doctor detoxes in the two-hour premiere.

"Accidentally on Purpose" (7:30 p.m., WBBM-Channel 2): If you've missed Jenna Elfman on the airwaves, you're in luck.

"Dancing With the Stars," "Castle" (7 and 9 p.m., WLS-Channel 7): Season premieres.

"Greek" (8 p.m., ABC Family): Casey supervises a non-alcohol party night during a campus Dry Weekend. I don't remember those.

"Phineas and Ferb" (9 p.m., Disney): Jennifer Grey guest-voices on this excellent series about two boys, their incredible engineering skills, and their undercover platypus. I could not be more excited.