A girl needs her beauty sleep.

But she also needs to know whether or not Tom Scavo is cheating on Lynnette. She needs to know whether or not Denny survives his heart transplant. And, most important, she needs to know, once and for all, why Oceanic Flight 815 crashed.

Which means this girl isn’t getting any sleep of late.

The person who invented the two-hour season finale should be shot. Maybe Michael from “Lost” could do the deed. Whoever it is probably owns stock in under-eye concealer. Or Green Mountain Coffee. Or No-Doz.

For a woman who doesn’t have cable and who – up until “Alias” hit the scene – rarely watched TV, my recent addictions are bad enough. I can’t get enough of “Desperate Housewives,” “Lost” and “Grey’s Anatomy,” which I’ve fondly dubbed “Grey’s of Our Lives.”

In theory, two straight hours of guilty goodness is fabulous, but in practice, these finales are killing me. If they started at 8, I wouldn’t need to mainline caffeine. I could make it through the afternoon without considering a 3 o’clock nap. My productivity would go WAY up.

Or not. I’m still gabbing about the Meredith-McDreamy hookup. I spent a better chunk of my lunch hour rehashing Jack’s death on “Alias.” And I guarantee tonight’s “Lost” finale will leave me reeling. What with Michael’s betrayal, Sayid’s intelligence and Eko’s unwavering faith in the button, it can only end badly – especially with the boat in the promos. Look how well things turned out the last time that happened.

Will it be worth two hours of my time? Absolutely. Even if it means another sleep-deprived night.

It’s a good thing it all ends tonight. I’m starting to look a little tired.

Then again, I’m also starting to look forward to September. (Kristen Andresen, BDN)