WHO WOULD have imagined that the most popular "F-word" dished by the Cosmo Quartet would not be "Fashion," would not be "Flirt," would not even be "F---," but would be . . . "Forgiveness"?

Back after four years, the "Sex and the City" girls - one of America's great cultural sexports to the world - have aged like parmesan. They're starting to think like me. Call me Mr. Big.

Now in their 40s (with grande dame Samantha "celebrating" 50 with a botox birthday cake) they've found a new depth, or at least an unexplored layer, in the movie that opened over the weekend to the squeals of single women and the rapture of gay men.

Or vice versa.

On HBO, "SATC" was a Sunday-night delight, a sweet cannoli before bed, an hour to share with Baby Cakes, who is part Carrie and part Charlotte.

At 2 hours, 28 minutes, the movie is like using a wheelbarrow to move a Chihuahua. The vehicle is heavier than the cargo requires.

The Forgiveness theme swirls around witty Carrie, who's mad at Big, and grouchy Miranda, who leaves husband Steve because he's had an affair to which he voluntarily confesses and begs forgiveness. Simultaneously, Miranda wrongs Carrie in a minor way and needs forgiveness herself, and, in a plot stretch, Samantha needs to forgive herself.

There are some plot knots too tough to swallow, but I will step back so as to not reveal too much. Let's go to Steve's stunning confession of infidelity.

How did he miss the chapter in The Gentleman's Guide that says, "Never admit it. Even if she catches you in bed doing it with a hoochie mama, deny it."

Call this the Clinton Credo. (Nowadays, I must specify that I mean the Bill Clinton Credo.)

Deny, deny, deny.

Confession may be good for your soul, but it makes her feel bad, as it did Miranda. You must lie to protect her feelings. (See "Clinton Credo," above.)

It is ironic that the only member of the fashion-addicted Cosmo Quartet - tottering around on skyscraper heels while living in stockyard apartments - who is truly happy is Charlotte, the least cynical of the stilettoed sirens. What is the message when happiness goes to the stereotypical Old-Fashioned Girl who married a fat, bald shlub with no artifice and a heart of gold? Has "SATC" gone all mushy? Is it admitting that there is a greater verity than Versace?

Charlotte's happiness nullifies the shallow values in the "SATC" girls' operating manual that endorses biting on looks and/or wealth and/or hopping into bed with the best available body. The other three always just tolerated Charlotte, with rolled eyeballs, for her naive optimism.

When the show came on 10 years ago, pickup-bar talk changed. Instead of "What sign are you?" it was "Which girl are you?"

The sassy Carrie, the innocent Charlotte, the workaholic Miranda, the sexual predator Samantha.

Girls, which one are you? Guys, which one do you want to date?

Are you sure?

In the brief and bitter sojourn between my marriages, at the peak of "SATC" 's popularity, I met them all, plus some the show didn't introduce to America: Bubbly Airhead, Damaged Goods, Manic Maiden, Non-Stop Talker, Suspicious Stalker, Hot Ghetto Mess.

I even met a Manayunk woman who told me straight off, "I'm Samantha."

I took her home, where she scared the hell out of me.

I guess I wasn't Big enough. *

E-mail stubyko@phillynews.com or call 215-854-5977. For recent columns: