8-10 p.m., Sunday-Monday
Fox

Boy, it's getting tougher and tougher to review these returning shows. "Don't reveal this!" "Don't mention that!" Sheesh. Just popping in the "24" DVD caused me a brief moment of panic, as if the simple act of watching the thing was a big no-no -- because I'd be ruining it for myself.

The cover sheet that accompanied the review screener of the mega-intense first four hours of Season 6 that premieres (as last year) in a pair of two-hour chunks spells out how we critics are forbidden from discussing "the exact nature of how Jack (Kiefer Sutherland) is expected to sacrifice himself, and what happens in the final minutes of the first and fourth hours." OK, so I won't. I probably also shouldn't talk about that big chili dog Jack eats in Episode 3 and the havoc it wreaks on his digestive system. And do they expect me to say nothing of the firecracker that's planted inside Jack's ear by that wily terrorist and how it causes him to walk around thinking he's a shuttle mission about to lift off?

Just joking, folks. What am I actually allowed to write about the reigning Emmy champ for outstanding drama and lead actor (Sutherland)? Let see ... well, once again, it's heart-in-your-throat time. This show consistently grabs your innards, shakes and doesn't stop. And the year opens with a darker and more disturbing story line than ever, with Jack being released after two years in a Chinese prison and looking entirely defeated.

He isn't, of course, but you can tell he's about had it with this hourly courting-of-death stuff and has his mind set on a decade or so at Club Med Cancun. But the major cities in the U.S. have been under terrorist siege for nearly a year, and only Jack can save our pathetic superpower butts. There's a new president (DB Woodside) but the same old harrowing minute-to-minute frenzy of action. This remains a superb, positively riveting TV drama, however repetitive the themes and grandly implausible the scenarios. Just don't ask me to say any more. I believe it's a matter of national security at this point.