After all the bells, whistles and false alarms, the heir to David Letterman on NBC’s “Late Night” will indeed be a virtually unknown, 30-year-old producer for “The Simpsons” named Conan O’Brien.

A former “Saturday Night Live” writer and the first choice of his former boss on that show, new “Late Night” exec producer Lorne Michaels, O’Brien has been rumored to be a top contender the last two weeks (Daily Variety, April 16). He was officially given the high-profile slot Monday after a week of discussions between NBC and Garry Shandling that have left a number of red-faced media outlets in their wake.

The job was apparently Shandling’s if he wanted it. Sources say the comic (and, at one point, regular guest host of “The Tonight Show” when it starred Johnny Carson) turned down the multimillion-dollar opportunity primarily due to logistical concerns. In particular, NBC is intent on launching the new series by late summer, while Shandling will be tied up producing his acclaimed HBO series “The Larry Sanders Show” through the summer.

The Shandling camp apparently felt such a scenario wouldn’t provide enough time to get the new show up and running, and Shandling’s manager, Brad Grey, called NBC brass Monday to take Shandling’s name out of contention.

That left O’Brien, who always had been Michaels’ first choice. In addition, he reportedly impressed NBC officials with a tryout earlier this month in which he performed a brief monologue and interviewed Jason Alexander and Mimi Rogers. The O’Brien-hosted show is expected to place greater emphasis on performances and sketch comedy while downplaying the straight talk element, although such decisions are still in an extremely nascent stage.

The new “Late Night” (that portion of the name is expected to remain) will still originate from New York. Michaels, like Shandling, is represented by Grey, while O’Brien is handled by Gavin Polone of United Talent Agency.

All parties were declining comment in anticipation of a last-minute appearance by O’Brien on Monday night’s “The Tonight Show With Jay Leno” to introduce him to the public.

As previously noted, although O’Brien was Michaels’ first choice, NBC officials felt compelled to seek a bigger name — like Shandling — to make the revamped “Late Night” more appealing to affiliates.

Though sources acknowledged that an unknown will be tougher to sell to affiliates and advertisers, they pointed out Michaels’ skill at finding fresh young talent in the past, including the parade of one-time unknowns-turned-movie stars he introduced on “Saturday Night Live.”

O’Brien’s youth is also seen in some quarters as a potential asset — making him a sort-of talk show host for the Pepsi/MTV generation, in contrast to the 40-something Leno, Letterman and Shandling.

Letterman once unknown

Others noted that Letterman was relatively unknown when his late night show was launched, though he had the benefit of doing so in a then-little-watched time period, while new shows (such as Letterman’s CBS show, the new “Late Night” and Fox Broadcasting Co.’s “The Chevy Chase Show”) will all be subject to intense scrutiny because of media interest in the daypart.

O’Brien began as a performer with the improv troupe the Groundlings before becoming a writer on HBO’s “Not Necessarily the News,” “SNL” and, for the last two seasons, “The Simpsons.” A 1985 Harvard graduate, he served as editor of the Harvard Lampoon during his college days.

How the choice will play with NBC affiliates remains to be seen, but the network will doubtless pull out all the stops touting the series at its upcoming affiliate convention next month in Orlando, Fla., when the network will also unveil its fall prime time schedule.

Currently, “Late Night,” like “The Tonight Show,” enjoys near-100% U.S. coverage, and the network will fight hard to stave off late night preemptions.

Three-month search

The selection of O’Brien ends a three-month search that officially began Jan. 14, when NBC confirmed — amid enormous media attention and hoopla — that Letterman would indeed leave “Late Night” to host a new CBS show opposite “Tonight” and that Michaels would exec produce his replacement.

CBS is expected to introduce Letterman’s new show Aug. 23, and he’ll host his last “Late Night” episode on June 25.

NBC has yet to say what will fill the breach, though there’s been talk both of repeating “Late Night” and slotting repeats of “The Tonight Show Starring Johnny Carson.”

At one point, several months before a decision on the Letterman move became final, Dana Carvey was seen as the heir apparent to “Late Night” and signed to an overall deal with the network. (Letterman, in fact, at one point introduced him as being “a heartbeat away from hosting this show.”)

Carvey, another Grey client, reportedly got cold feet about committing to the late night grind after his movie career took off — propelled by the box office success of “Wayne’s World”– leaving NBC without a ready replacement when the Letterman situation came to a head in January.

Shandling, meanwhile, continues working on new episodes of his talk show spoof “Larry Sanders” and has various other projects in the works.

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