Every pundit and anchor star will turn up for extravagant Election Night TV coverage. It will not only be wall-to-wall, it will feature dueling computer walls, to explain who's winning and where.

But, even with CNN map wizard John King, it won't mean a thing if it ain't got that ring - of truth, that is. Embarrassed networks learned that lesson well in 2000. And that truth this year comes not from some glistening studio or famous face, but from a secure chamber that sounds like it should be in a horror movie:

The Quarantine Room.

Which is where the networks' election polling data will come from.

Results flow continuously on Election Day from across the country to a central analysis center, and then on to the networks. In 2004, early and incomplete data leaked, leading to reports that John Kerry was winning the election. Nobody wants that to happen again. So all the data will be released to only one place.

"Somewhere in New York City, at an undisclosed location, there's a quarantine room, in which up to three members of each network will be present, reviewing the data, starting in the morning," explained Sheldon Gawiser, NBC director of elections.

"They will be locked in that room until 5 p.m. They will have no cell phones and pagers. The wireless will be turned off on all their computers. If they go to the bathroom, they have to have a monitor."

The last two elections have not been good ones for presidential vote-counting on TV. Bad exit polls fueled the 2000 first-Gore, then-Bush, then-we-don't-know fandango, resulting in a new organization doing the work.

That helped assure that none of the networks called a single state wrong in 2004, but it didn't stop pundits and Web sites from speculating throughout the day that Kerry was winning.

"There's an itchy-fingered demand for what we're providing," said Joe Lenski, executive vice president of Edison Media Research, one of two firms working for the National Election Pool to conduct exit polls. "The idea is to just give access to the people that are too busy to talk to anyone else, and the data stays where it should be. . . .

"We have to manage the release . . . so that early data that can be misinterpreted is not out there for people who don't understand. . . . The professionals here know how much they can rely on this data."

A steering committee from ABC, CBS, NBC, CNN, Fox News and the Associated Press oversees the National Election Pool, which has contracted with Edison and Mitofsky International not only to conduct exit polls on Election Day but also to contact people who have voted early in the 34 states that allow it. Early balloting is a significant force this year - as much as a third of the total vote, some experts predict - with people already standing in long lines to cast votes in such swing states as Florida.

"You have to account for those folks somehow," Lenski said, "because they're not going to be at a polling place on Election Day," when he will have more than 3,000 interviewers scattered across the country. In addition to having worked the primaries, most of them have experience doing polls year in and year out on a raft of topics at the exits of movie theaters, airports, concerts, even school buses.

Their data will be added to results from 10,000 people contacted by telephone who said they voted early.

All of it flows to an analysis headquarters above an old Woolworth's in Somerville, N.J., where the data will be examined by a dozen professional pollsters, professors and numbers-crunchers, and then be forwarded to the Quarantine Room.

There, statisticians and "Decision Desk" experts from the networks, such as University of Pennsylvania political-science professor John Lupinski of Ardmore, who has done this drill for NBC on almost all of the primary nights this year, develop their own informed takes and story threads for evening coverage.

They will be released from quarantine at 5 p.m. Then they'll rush to their respective work stations, where even more savants will scope out the numbers.

It's the network news divisions' night to shine, literally.

ABC will be running its coverage in Times Square on its 43d Street JumboTron. Fox News, debuting two new high-definition studios, will beam its signal down from across the street on the Square's huge Astrovision monitor.

Once again, NBC will transform Rockefeller Plaza into Election Plaza, with outdoor anchor booths, election numbers beamed up the side of its headquarters at 30 Rock, and a huge map on the surface of the Wolman Skating Rink, which scuttling minions will fit with red or blue state cutouts as the results are called.

That antique technology contrasts with CNN analyst John King's Magic Wall, a computer screen with an infinitely variable map that responds to its operator's touch and has given viewers new insight into the electoral process this election cycle.

King originated the device. Now everybody but cash-starved PBS ("We've got the best minds in the room, not the best gadgets," says Linda Winslow, executive producer of The NewsHour with Jim Lehrer) has one.

Saturday Night Live's Fred Armisen borrowed NBC's computer map to do a funny riff on the gizmo last month, drawing a cat on the Rocky Mountain West, breaking Oregon off into the Pacific Ocean, and sliding New Hampshire down Mexico way.

"Fred did such a good job. I'm worried about my job security," said CNN's King, who explained that his gadget comes from a company called Perceptive Pixel and is called a Multi-Touch Collaboration Wall. (You can get your own at Neiman Marcus for $100,000.)

"I have the best job at the network," King said. "We all learn the Electoral College stuff in civics class, but the map and wall can show how presidential politics is a very complicated jigsaw puzzle. It's a visual way to explain and to take people into a state like Pennsylvania, for instance, where counties and voting precincts are so drastically different."

King is a big fan of Montgomery County. If Barack Obama wins strongly there, King has said, that's an indication he might win enough votes in suburban St. Louis and Cleveland to carry Missouri and Ohio and win the election. If John McCain puts Montgomery County in his pocket, the election might go the other way.

Each network will have different criteria for making its calls, which start with results from about 110,000 exit-poll interviews that will go to the Quarantine Room. If they are overwhelming in a particular state, a network might call the election based on them alone. If not, the poll data are combined with actual votes from about 2,000 sample precincts. If things are still too close, networks can wait for tallies from every county in America.

All have agreed to reveal no winner from a particular state until all its polling places are scheduled to close.

Before 2000, when presidential elections in the modern TV era had followed the historical pattern of not being particularly close, speed was of the utmost importance as the networks jockeyed for prestige.

Not any longer.

"I promise you, accuracy is what is important to all of us," said Rick Kaplan, executive producer of the CBS Evening News With Katie Couric and the network's election and special events coverage. "I absolutely don't care when others make their calls. I really don't."

"I have to be right," said NBC's Gawiser. "I've made three mistakes in 30 years of doing this, the most famous being in 2000.

"It's not fun making a mistake."