Night after night, Larry King Live has been a pillar of American culture.

On Thursday, television history will be made. One of the legends of the small screen will be broadcast live at precisely the moment that his trousers fall down.

At least that's what will happen metaphorically. Larry King will hang up his famous braces.

For 25 years, night after night, Larry King Live has been a pillar of American culture, as comforting and dependable as Mickey Mouse and Hershey. But even cultural pillars can grow structurally unsound; in the case of King some would say that happened years ago.

CNN is being tight-lipped about the guests for the final show, which goes out at 9 p.m. [U.S. eastern time], revealing only the names of fellow TV hosts Ryan Seacrest and Bill Maher while withholding those of the 14 other participants.

Some will be politicians, CNN says. Which raises the possibility that Mario Cuomo will be among them — a pleasing touch were it to happen as Mr. Cuomo, then New York Governor, was Mr. King's very first guest on June 1, 1985.

It also holds out the possibility of Mr. King being rejoined by Ross Perot, who helped put Larry King Live on the map in 1992 when he declared on the show that he was running for the presidency. There again Al Gore might also be in attendance: the debate between him and Mr. Perot in 1993 was arguably the show's finest hour — transfixing a nation and attracting 20 million viewers.

For media watchers like Mark Feldstein, a former CNN correspondent, now journalism professor at George Washington University, such TV events were a boon to the network as it set out as the first 24-hour news operation. “In the early days CNN was a very traditional news outlet,” he said. “To have a fluffier talkshow like King's increased the pool of viewers and his very soft interviewing style brought in big names.” Those big names were drawn from the worlds of politics and entertainment. In politics his guests included Margaret Thatcher, whose spongier, non-iron side he enjoyed trying to reach; Vladimir Putin, the Russian Prime Minister, who earlier this month returned to the show saying “there is just one King”; and every U.S. President since Richard Nixon.

Entertainers included Marlon Brando, interviewed at his home in Beverley Hills in 1994 with the memorable ending in which the actor gave Mr. King a full-on kiss. More recently, in June, he hosted Lady Gaga, asking her point blank: “Are you with men more or women more?” (To which the singer replied: “Love comes in many different forms.”) Simple, direct questions like that one were Mr. King at his best. He was particular about asking short, one-sentence questions and keeping his own ego in check. Less happily, he increasingly came across as a tiger turned toothless patsy. “Are you enjoying the job?” he asked Mr. Putin, then Russian President, in 2000.

At worst, he could be outright ignorant, boasting that he liked to go into interviews “fresh” with minimal research and never reading his guests' books. On occasion he fell flat on his face, as when he asked Jerry Seinfeld, star of one of the most popular hits in U.S. television history, whether his show Seinfeld had been cancelled.

“You think I got cancelled?” a disbelieving Mr. Seinfeld replied, asking King “Do you know who I am? ... can we get a resume in here for me?” “By the end King had become an almost vaudevillian relic of his past glory,” Mr. Feldstein said. “He became a throwback to an earlier era of broadcasting and an anachronism with the rise of the internet.” Once tonight's show is over, and the lights dim on Mr. King's trademark dotted map set and his vintage microphone, the spotlight will switch to his successor, Piers Morgan. The former editor of the Mirror newspaper in Britain may not have a hard act to follow, despite the legendary standing of those braces. But his new show, Piers Morgan Tonight, will be under intense pressure to improve the ratings, which in recent years has slumped from that Perot-Gore peak to a miserable nightly average of 700,000. — © Guardian Newspapers Limited, 2010

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