Extra half-hour places finale outside of primetime

Six mysterious seasons of “Lost” will culminate with one final, explosive moment on May 23. Yet those last minutes won’t have any impact on ABC’s primetime ratings.

Alphabet net’s decision to expand the “Lost” finale by half an hour — from 9 p.m. to 11:30 p.m. that Sunday night — now puts what promises to be one of the biggest moments of the TV season outside of primetime.

That might seem like an odd decision to make, given that every ratings point counts as the networks sprint toward the May sweeps — and 2009-2010 TV season — finish line.

But in the case of “Lost,” the network is able to sell more commercial time with the extra half-hour — which is why they didn’t balk when producers called from the edit bay asking for additional time.

Ditto ABC’s affiliate stations, which were given additional ad time in exchange for the show pushing into local news time.

Given the costly price tag of a “Lost” finale, coupled with a “Lost” retrospective (airing from 7 p.m. to 9 p.m.), those extra ad dollars will help amortize the cost of the evening. (ABC is also repeating the “Lost” finale on May 29.)

Besides, the net figures, big events spill out of prime all the time. The Oscars rarely announce the best picture before 11 p.m., for example.

According to insiders, ABC execs were still concerned with airing the final “Lost” scene so late — essentially at 11:29 p.m. But the idea of starting the finale at 8:30 p.m. was nixed, as viewers aren’t in the habit of tuning in to a longform program at the half-hour mark.

The other downside: “Jimmy Kimmel Live’s” special Sunday night “Lost” panel won’t hit the air until 12:05 a.m. “Lost” stars past and present Naveen Andrews, Nestor Carbonell, Alan Dale, Jeremy Davies, Emilie de Ravin, Michael Emerson, Matthew Fox, Daniel Dae Kim, Terry O’Quinn and Harold Perrineau are all confirmed to appear.

“Jimmy Kimmel Live: Aloha to Lost” will also include the first look at three alternative final scenes. Executive producers Damon Lindelof and Carlton Cuse have previously promised to go into hiding after the “Lost” finale airing, and won’t be live in the studio to explain themselves.

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