It's a big night for TV fans. One new series debuts; there are seven — count 'em, seven — season premieres of returning series; and there are four hours of new episodes of other series.

And that's just on the broadcast networks.

Here's a look at what to expect:

The Big Bang Theory (second season premiere, 7 p.m., Ch. 2) hasn't lost a beat from its writers' strike-shortened first season. This is laugh-out-loud funny stuff.

You'd be well advised to record it so you don't miss any jokes because you're laughing too hard.

In tonight's episode, titled "The Bad Fish Pardigm," Penny (Kaley Cuoco) and Leonard (Johnny Galecki) go on their first date, and things don't turn out all that well. And Sheldon (Jim Parsons) — who's one of the funniest characters on TV — gets caught in the middle when he has to keep Penny's secret.

Dancing with the Stars (seventh-season premiere, 7 p.m., Ch. 4) opens with a two-hour extravaganza, with two more hours on Tuesday (when one couple will be eliminated) and still another hour on Wednesday (when another team will exit).

Two-time winner/Utahn Julianne Hough and her brother, Derek, are both back for another season.

Call me crazy, but I'm looking forward to seeing tart-tongued octogenarian Cloris Leachman perform.

Heroes ("Countdown to Premiere" special, 7 p.m., Ch. 5; third-season premiere, 8 p.m., Ch. 5) is back with a vengeance. And it hits the ground running. There's a lot going on in the first half of the two-hour premiere (which was screened for critics). And there's a lot more promised in the second half (which wasn't screened for critics).

I'm reluctant to tell you much for fear or spoiling it, but we do quickly discover who shot Nathan (Adrian Pasdar); what's up with Sylar (Zachary Quinto); what Peter (Milo Ventimiglia) is doing; and how Hiro (Masi Oka) is handling being the head of his late father's corporation.

And there's a huge development at the end of the first hour that could change everything.

There's been a lot of complaining about last season — a lot of criticism that wasn't really fair because the season was cut in half by the strike. But I'm very encouraged by the first hour of this season.

How I Met Your Mother (fourth-season premiere, 7:30 p.m., Ch. 2) opens the season with a quick answer to last spring's cliffhanger — will Stella (Sarah Chalke) accept Ted's (Josh Radnor) marriage proposal?