Don't miss the first 10 minutes of "24" on Sunday (7 p.m., Ch. 13).

I'm not kidding. Really. Don't miss it.

That, unfortunately, is about all I can tell you about the fifth-season premiere of TV's great roller-coaster ride. And not just because Fox is threatening me if I do, but because I don't want to ruin it for you.

Let's just say that one development in the show floored me. And a second development, which is only less surprising because it comes second. And the two are related.

Whoops, I'd better stop there. Don't want to ruin it.

When "24" wrapped up Season 4 nine months ago, our hero, Jack Bauer (Kiefer Sutherland), had just saved the world — again — and he had to fake his own death in order to prevent being turned over to the Chinese. (They were a bit ticked off at him for leading a mission into one of their consulates — a mission that inadvertently resulted in the death of a Chinese national.)

As Season 5 gets under way (two episodes air Sunday at 7 and 8 p.m.; two more on Monday at 7 and 8 p.m.), it's 18 months later and Jack has been on the run. There are only four people who know he's still alive, and all make appearances on Sunday night — former U.S. President David Palmer (Dennis Haysbert), former CTU operatives Tony Almeida (Carlos Bernard) and his wife, Michelle (Reiko Aylesworth), and current CTU computer geek Chloe (Mary Lynn Rajskub).

Without giving anything important way, let me just tell you that Jack is drawn out of, um, forced retirement in a way that's completely believable. (Well, believable enough, given that, at the end of Episodes 1-4, we don't really know what's going on.) And there's an enormous amount of excitement in those first four hours, complete with surprising twists and unbelievably tense cliffhangers.

In addition to a few familiar faces, there are some additions, including Connie Britton as Jack's new love interest, Brady Corbet as her son, Sean Astin as an officious CTU executive, and Jean Smart, who's fantastic as the first lady, who's not as mentally unstable as her husband thinks she is.

Every time a season of "24" ends, you wonder how the writers and producers can possibly top it.

Four hours into Season 5, it looks like they've done it again.

I just can't tell you how. You'll have to tune in on Sunday and Monday.

IT'S NOT UNUSUAL for networks and producers to ask those of us who review their shows not to reveal surprising plot twists so as not to ruin the surprise for viewers. It's a request I'm always happy to comply with.

Although, I've got to tell you, it's never been so hard to write about anything as "24." I truly can't tell you much of anything, because those big surprises in the first 10 minutes set the entire season in motion.