Los Angeles -- When NBC picked unknown Conan O'Brien to replace David Letterman as host of its "Late Night" show, most people thought it made about as much sense as the San Francisco Giants asking the team's water boy to take over in center field after Willie Mays left.
As it turns out, even Mr. O'Brien admits there are times when he asks himself, "What the hell have I done? Am I going to be able to do this?"
Yet, starting tonight, the 30-year-old writer-turned-performer will be host of "Late Night with Conan O'Brien," following in the steps of a show-business legend who made the time slot a gold mine for NBC.
The network took its lumps for putting so much faith in a young man whose only real performing work has been in the Los Angeles comedy ensemble known as The Groundlings. He has made a few TV appearances but nothing significant enough to label him a comedy discovery.
Mr. O'Brien, a former editor of the Harvard Lampoon and former "Saturday Night Live" writer, is well aware of how skimpy his portfolio may seem to most of us.
But after leaving "SNL" to write and co-produce Fox's adult cartoon hit, "The Simpsons," he was interested in trying his jokes on-camera for a change.
"I've never done anything like this," he said. "At times, that is sobering. But, overall, there's a feeling I have inside me that I can do it. The odds might be all stacked against me, but I feel I can do it."
Many suspect that NBC is trying to perform a demographic miracle with Mr. O'Brien. Still boyish and gawky (he's 6-foot-4), with a youthful comic sensibility, he seems most likely to appeal to the "twentysomething" crowd advertisers are desperate to reach, a group that even the hip Mr. Letterman may be too old to attract anymore.
"The fact that I turned 30 in April and I'm young to be doing this has made many people think I'm a voice for a new generation," Mr. O'Brien said.
"I may be. I don't know. I think it's possible to get too cerebral about these things."
What Mr. O'Brien is pretty sure he won't do, though, is try to hold onto the stay-up-late Letterman audience by copying the past master or using some of the comedy features, such as "stupid pet tricks" and "top 10 lists," that Mr. Letterman pioneered but NBC wouldn't let him take over to CBS.
"I'm a different person, you know," said Mr. O'Brien. "This will be a different show. I couldn't do Dave's show if I wanted to. I couldn't do Johnny Carson's show or Jay Leno's show. What I've got to do is Pat Sajak's show the best I can."
That, of course, is what NBC is hoping he won't do.
CBS tried to make an overnight talk show star out of game-show host Pat Sajak -- and it flopped. Most think that happened because Mr. Sajak wasn't funny enough and his show was like "safe and sane" fireworks: Too little bang for the bucks.
Lorne Michaels, the veteran producer and creator of "SNL" who chose Mr. O'Brien as the new "Late Night" host, is on the job to guarantee that won't happen. He wants Mr. O'Brien to climb out on the limb and shake it. Mr. O'Brien is more than willing to comply. He thinks the shows he's worked on -- from "Saturday Night Live" and "Not Necessarily the News" to "The Simpsons" -- ought to suggest how far from safe and sane his show is going to be.
"I think I have a playful sense of humor," he said. "People have often told me my sense of humor is somewhat absurdist, silly."
BTC Essentially, though, Mr. O'Brien wants to re-invent the talk-show format, to "try and find new ways to have fun with it."
Mr. Michaels likes to remind everybody that Letterman wasn't doing all his famous features the night he started "Late Night." They came out of lots of bold experiments and any number of failures. He thinks a performer with a writer's comic mind as fertile as Mr. O'Brien's ought to be able to find his own assortment of features over time.
The canny veteran producer also thinks the heavy competition among Mr. Leno, Mr. Letterman and Chevy Chase in the hour before Mr. O'Brien's show will take much of the heat off the newcomer and maybe distract those who might be eager to hoist Mr. O'Brien on his own petard right away.
Whatever happens, Mr. O'Brien thinks he has been treated much better than a water boy stepping into center field in the major leagues. Mr. Letterman wished him well on his farewell NBC show and Mr. O'Brien says "a lot of things that could have been nasty haven't been." He doesn't even fault the press for picking on him a little.
"My feeling is that if this show doesn't work for any reason, it'll be my fault," he said. "I think I've been given a lot of chances here."