Menachem Begin, bathed in TV lights, was hosting an impromptu press conference on his patio when suddenly he felt something groping at his trousers.

It was Peggy Whedon, producer of "Issues and Answers," trying to book Begin for the show. No one had expected him to win the 1977 election, and all of Whedon's equipment was set up to film Shimon Peres. By the time she got to the Israeli prime minister's little house, she was behind a beefy barricade of reporters and photographers. "I couldn't get near him. So I started crawling along the floor under the camera lenses and pulled on his pants leg." Would he appear? "Of course," said a startled Begin, but "get up off that floor."

On any Sunday, from the opening drum roll of CBS' "Face the Nation" at 11:30, through the wry cadences of David Brinkley on ABC's "This Week," to the closing credits of NBC's "Meet the Press" at 1 o'clock, a drowsy nation awakens to the sound of Washington's jawmills grinding through a week's worth of news. Several million Americans watch as the lumbering responses of prominent policymakers are hewn into tomorrow's headlines.

What they can't see are the six days of hustle, chutzpah and hyperacidity that precede every convening of our ritual Sabbath inquisition.

Each network wants to be on the See SUNDAYS, C4, Col. 1 SUNDAYS, From C1 cutting edge of the news, but each goes about it somewhat differently. "Our basic philosophy," says Dorrance Smith, executive producer of "This Week," which replaced "Issues" last November, "is that we're committed to a story every week, instead of an individual guest, and we're going to get whoever we need." ABC, with its hour-long "magazine" format, gears up for three or four hot topics a month, and then tries to recruit guests accordingly, depending on how the news is breaking. NBC and CBS focus their half-hours on one individual.

Joan Barone, producer of "Face," says, "I believe strongly that since we're the only interview broadcast on CBS News, we owe it to our viewers to get one policymaker who is in the news that particular week."

The Week's Work

"I'm not sure we've ever had a normal week," says Whedon, but in general each outfit starts compiling its roster of two to six potential guests by Monday or Tuesday. Producers confer with the show's anchors (Brinkley on ABC, George Herman on CBS and Bill Monroe on NBC) and various news executives.

But the process doesn't become molar-grindingly serious until Thursday, since, as Whedon says, "you call about 50 people to end up with one or two," who by then may already be old news.

By Friday the tension can peak, as ABC is finding out today. Smith had wanted to "do the Democrats" to coincide with the end of Ronald Reagan's first year in office, but "you can't get Carter, you can't get Mondale or Tip O'Neill or Teddy." So he booked William French Smith. But yesterday afternoon, the attorney general suddenly "changed his mind for no reason that he'll give us." At press time yesterday, producer Smith was still struggling to restructure the show and recruit 11th-hour Democrats.

At the other two networks, this week is a placid one. CBS will have Citicorp head Walter Wriston ("We've been working on him since last August," says Barone, "and this is the first available Sunday he had"); and NBC will carry Sen. Howard Baker, planned in advance as the curtain-raiser on Congress' return.

Schedules have become further unsettled by the advent of sophisticated satellite transmission, making possible last-minute changes like the Qaddafi connection. For the Dec. 6 show, ABC had booked Israeli defense minister Ariel Sharon, and had sent Whedon, who is now with "This Week," to Tel Aviv. But then reports of phantom Libyan "hit squads" broke, and "I got a call from the desk at 12:45 Saturday morning," says Smith. "Roone Arledge, ABC news/sports president thought we ought to consider going after Qaddafi." ABC's conviction grew after Brinkley, lunching with Sen. Howard Baker on Saturday, saw that Baker had suddenly acquired Secret Service protection. Smith sent a producer to Tripoli, and got correspondent Lou Cioffi on the case from the Mideast.

By 5 a.m. on Sunday, word came back that Qaddafi had agreed to the interview, and "at that point, the problem became technical," Smith says.

Smith had no voice contact with Qaddafi's private office, his nearest staffer was an ABC producer in another building, and the clock was ticking toward the 11:30 air time. "By 11:25," Smith says, "we finally see a picture of a room and an empty chair." Smith was getting agitated, but "I finally saw him 4 1/2 minutes before we went on."

Because the Qaddafi shoot was chancy, Smith had covered his bets with a couple of studio stand-bys: Sen. Daniel Moynihan and former CIA director Stansfield Turner. Moynihan made it on the air; Turner didn't. That's the way it is in the electronic agora: "He understood what the ground rules were before he came on," says Smith.

Cancellations can send networks scrambling, and producers worry constantly about weather and air travel. That's why, Barone says, one of CBS' "non-negotiable demands" is that the guest be in the city of origination on Saturday night. Some try to cheat.

Whedon recalls the time she scheduled Sen. Jacob Javits who decided to fly down from New York Sunday morning, and his plane was grounded by fog. He called at 10 a.m. to cancel. Whedon immediately called the Washington home number of Sen. Hubert Humphrey, who "had rescued me a couple of times." Muriel Humphrey reported that her husband was out playing baseball in Rock Creek Park with some Minnesotans. "Don't have him call," said Whedon, "just tell him to get in here." Forty minutes later, Humphrey "arrived in this baseball outfit, covered with dirt." Whedon stripped the cameramen and engineers for a jacket, shirt and tie, beneath which Humphrey wore baseball pants and cleats. The show aired on time.

Getting Bumped

Such abate-and-switch snafus develop only once or twice a year. More often, what happens is that the scheduled subject becomes second choice when breaking news shatters priorities. This results in "bumping" the original guest. Former Democratic Party chairman Robert Strauss survived a rare form of calamitous double-bumping. "When Sadat went to Jerusalem the first time," CBS' Barone says, "we put in an invitation for him to appear. He did not accept until very late in the week. Meantime, we had invited Bob Strauss. We called and asked if he would mind if we postponed him. He was extremely gracious, and we rescheduled him for six weeks later. But that week, Menachem Begin came to Washington very unexpectedly. We went to Strauss again and said, 'Uh, would you mind? . . .' We had him on the very next week."

Strauss, a veteran of many Sunday inquests, says, "I guess if you're insecure, maybe it shakes you up. But if I had the choice between Anwar Sadat and me, I'd take Sadat. I'm always around."

So he is. Strauss was asked to appear as the guest on the full-scale dress rehearsal for "This Week" one Saturday afternoon when Arledge came down from New York. Strauss admits that he's got the knack: "It's sort of a trick, sort of like working that cube." Mike Mansfield has it, he says, as does Jim Baker. But some are "too windy, not candid enough, too timid or too uptight." Willingness to talk with putative candor is a principal criterion in choosing guests.

Many are called, but few are chosen. Some are impossible: "You'd love to get Soviet foreign minister Andrei Gromyko or president Leonid Brezhnev," says Smith. Some are overlooked until it's too late: "I wish we had had John Lennon," says Barone. Some are almost too available. Often the White House decides to "send out the troops," as ABC's Smith puts it, to promote an administration policy. "They know what they're doing over there," says Smith, and former national security adviser Richard Allen agrees, recalling how "when there's a message to be put out," the White House team, led by communications director David Gergen, mounts a "quite well-orchestrated effort."

On Nov. 22, Defense Secretary Caspar Weinberger was on NBC, White House counselor Ed Meese on CBS, Secretary of State Alexander Haig on ABC. On Dec. 20 Weinberger was on ABC, Haig on CBS, Meese on NBC.

Although "we always have the right of refusal," Smith says, it's difficult to turn down a major Cabinet member, so "then the burden is on us to ask the right questions." The practice is an old one. Robert McNamara finally consented to appear on "Meet the Press," says Betty Dukert, the show's producer, only when "LBJ urged him to do it." The outgoing defense secretary perplexed the republic by quoting T.S. Eliot.

But on about half the Sundays, all three networks will be bidding for the same bodies, as they did earlier this month for William Clark, Allen's designated successor, who prudently demurred. And in the dog-eat-puppy world of Washington news, first-come may not be first-served, and one phone call is rarely enough. For Clark, Whedon "called, sent a telegram and hand-delivered a letter" -- just for openers.

"For certain 'stars'," like Defense Secretary Caspar Weinberger and other high-ranking Cabinet members, says Whedon, "we have a standing invitation." And for others, producers will start "general contacts" weeks before a possible appearance.

But the apparent persistence record is held by NBC. "Meet" negotiated for 13 1/2 years to get then-representative Wilbur Mills on the program: a total, according to Dukert, of 30 phone calls, one personal meeting and 28 letters to and from Mills, who eventually developed severe Potomac fever and appeared in June of 1971. But there are risks. After a protracted courtship, NBC finally secured Interior Secretary James Watt, who was then bumped at the last minute when Anwar Sadat was assassinated: "Just not a good week," Dukert says, "to be talking about national parks and the environment."

Picking the Panel

By the end of the week, each network has chosen its "outside" panelists to fit the particular guest. ABC's interviewers sometimes include Washington Post executive editor Benjamin Bradlee, columnist George Will, former State Department spokesman Hodding Carter and Karen House from The Wall Street Journal. CBS picks one print journalist who regularly covers the guest to make up its panel of three; NBC does the same to total four. Only the network correspondents, however, receive the background packages (as much as 100 typed pages, says Barone) that researchers prepare by Friday afternoon.

Special guests mean special panels. When "Face" booked Muhammad Ali in 1976, CBS discovered that it had three former Golden Gloves contenders in its stables: Jed Duvall, Barry Serafin and Fred Graham. But the simpatico group didn't stop Ali from taking stentorian umbrage at Graham's question about how Ali could reconcile his female friends with his strict religious convictions. Ali drew himself up into a formidable bulk, the camera went in for a tight shot, and the champ snapped, "I was told this was a high-class show!"

At NBC and CBS, once the show is on the air the next 22 1/2 minutes are out of the producer's control, except for the decision to roll credits at the end, depending on how closely the timing works out. "I often find myself shouting at the screen," says Barone, who like Dukert gets angry at guests who are long-winded (known in the trade as "filibustering") or purposely vague and unresponsive. Corporate executives, Barone says, tend to be the chief offenders, and the truly turgid are not asked to return unless "they're so noteworthy that you have to."

But part of "This Week's" flexibility comes in producer Smith's ability to cut off a guest who is gusting or simply has run out of things to say. Sitting behind the lavish control booth, Smith is connected by intercom to Brinkley, and "there's a certain point in each show when I tell David in his ear, 'As far as I'm concerned, you're on your own time now.' "

The Ratings Race

"This Week" replaced "Issues" on Nov. 15. The week before the premiere, David Brinkley inveighed against the "drab and repetitive" format of the Sunday shows. "In the first 15 minutes," he said, "you hear what the politician, or whoever, has to say; in the second 15 minutes, you hear it again. There tends to be too little perspective, too little analysis, too little focus." By using a "flexible" format mix of hard news, a background feature by James Wooten, the interview with one or more guests and a following panel discussion, Brinkley said, "we're planning to change all that."

Yet for all the competition, the ratings often are nearly the same. According to Nielsen computations, on Sunday, Jan. 3, "Face" was in first place with a 4.4 Nielsen rating (about 3.6 million homes) and a 16-percent share of the sets in use. "Meet" had a 4.2/14 and "This Week" a 4.1/13. The difference between the high and low figures represents about 200,000 homes -- "no significant difference," according to a Nielsen official.

"Meet" has the unique aggravation of a floating time slot: 12:30 for most of the year; noon during football season. "We're always glad when it's over," Dukert says, since "Meet" loses some stations to the pigskin. But when NBC carried the Cincinnati-San Diego playoff on Jan. 10, "Meet" had former quarterback Rep. Jack Kemp, who scored a 6.0/17, breaking far away from CBS' 3.3/10 and ABC's 4.6/12. Kemp was no doubt a good draw; but the fact that the AFC championship game was on at 1 p.m. sure didn't hurt.

The guest is a significant factor in the ratings. Naturally networks often prefer to get a commitment enough in advance to promote the coming show, and producers will go to extreme lengths to keep those dates. When Nguyen van Thieu became president of Vietnam in 1967, Dukert got his promise to do the show on the Sunday following his election. But when she arrived in Vietnam, she found Thieu waffling. "He said he wanted to wait a week until the ballots were officially counted," says Dukert, who tracked him down at a local TV station where he was about to go on.

She sprinted through a phalanx of armed guards -- "it's the one time I think being a female was an advantage" -- and "got through just before the doors locked." Wheeling past more guns, she was stopped by Thieu's press secretary, who asked what she was doing. "I said I just wanted to say hello."

Buttonholing the president after his broadcast, Dukert convinced him that it "would be a big mistake to wait, since it would cast some doubt on the validity of his victory." Thieu saw the wisdom of that, and changed his mind. But he would not agree to the ground rules, by which he would appear jointly with vice president Nguyen Ky. "Have you ever interviewed an American president and vice president together?" Thieu asked. Dukert got the picture -- as well as the guest and surprise headlines in the States: "Thieu Pushes Ky Off TV Program."Last-Minute Changes

Sometimes no amount of persuasion will work. For the Nov. 15 kick-off broadcast of "This Week," ABC had a commitment from David Stockman. But in the chaotic climate produced by William Greider's interview with the budget-meister in The Atlantic, Stockman cancelled at noon on Friday the 13th, a decision unaltered by Whedon's impassioned Friday-night plea to Stockman's press secretary.

Because of "This Week's" topic-oriented format, ABC had to go with a budget-related show. Jim Wooten had already prepared an elaborate background report on Stockman, including interviews with his mother in Ypsilanti, Mich., and shots of the farm he grew up on. So "we re-structured Wooten's piece to focus on Stockman's program and supply-side economics," Smith says. David Gergen called ABC and "offered George Bush when they pulled Stockman back, but we turned him down," hastily recruiting instead a guest troika of Felix Rohatyn and Sens. Ernest Hollings and William Armstrong, "all of whom took different positions on this topic. It was not the show that we had ever planned to produce." Stockman will finally appear on Jan. 31.

Some are thought to hold specific grudges. Richard Allen gave "Meet" its biggest coup of the fall season by appearing on Nov. 29 and announcing his leave of absence. All the networks had bids in for Allen, some well in advance. In early September, NBC's Dukert and her husband had attended a press screening of "Absence of Malice," where Dukert's husband ran into Allen and the two of them started "chatting about Notre Dame." Dukert grabbed the opportunity to solicit Allen for the show, and anchor Bill Monroe, who was also at the screening, repeated the invitation. But it was not until Thanksgiving Day that Dukert learned that Allen "was beginning to get itchy to do a longer interview." She called Monroe, who called Allen again.

Meanwhile, CBS didn't have much of a chance, since Allen had appeared on "Face" in October and is widely believed to dislike CBS correspondent Robert Schakne. (Not true, says Allen, although: "How can anyone be crazy about Robert Schakne?") ABC felt it had a better shot. Smith says, "I talked to him Thanksgiving Day and he said that he'd come on, that he was looking forward to it." But that night, ABC news carried a report by Carl Bernstein that detailed Allen's "extensively documented history of difficulty in separating private business from official business." Smith says Allen called him on Friday to say that the Bernstein story "had upset his Thanksgiving dinner and as a result he was mad at ABC," but waited until Saturday night to cancel formally. Allen says there was no promise and no grudge, although mentioning that his family "en masse" had watched the Bernstein report with profound displeasure.

Allen says, "I didn't say yea, nay or boo" to any network until Saturday, when "Meet" got the nod. Allen bumped scheduled guest Vernon Jordan of the Urban League. "I felt badly about that," Allen says, and called Monroe to convey his apologies to Jordan. Hitting the phones, ABC came up with Treasury Secretary Donald Regan and CBS had Sen. Pete Domenici. But NBC made the news.

"If you do your job well, you make headlines," says Dukert. But the jawmills will always find something to grind. Sometimes, says ABC's Smith, "we ought to just come on and say, 'Look -- we've read all the wires and there's nothing happening at all this week!' But no: Your job is to put together 52 weeks a year of fascinating television. And somehow we're gonna do that."