A close-knit band of friends and colleagues around Bill Clinton at the time of the Monica Lewinsky affair will speak publicly for the first time of their disbelief and sense of betrayal this month in a much-anticipated four-hour documentary about the former US president.

The two-part biography, which premieres in Britain and America on 20 February , chronicles Clinton's struggle with his unruly libido from the beginning of a political career he was determined would take him to the White House. His loyal adviser, the pollster Dick Morris, will tell of the moment Clinton rang him just before evidence of his affair with Lewinsky was about to be made public.

"Bill said to me: 'Ever since I got to the White House I have had to shut down my body'," says Morris, adding that Clinton told him he had been weak in the case of the 23-year-old intern and had done enough with her to be in serious trouble. He then asked Morris to conduct polls on how he should handle the crisis. Ken Gormley, a legal expert working in the White House, also recalls the sexual tension between the president and Lewinsky. "There were almost these sparks flying between them from the first moment when they saw each other," he says.

Those who worked with Clinton on his initial bid for governorship in his home state of Arkansas, campaigning alongside his wife Hillary, refer to his involvement with a long queue of women. One campaign chief remembers dealing with "25 women a day" who came into the office looking for Clinton, while Betsey Wright, the politician's trusted political aide, recounts how she eventually presented him with a list of girlfriends he had to deal with before he could stand as governor. "It became clear it was not the time to do it," she says.

As a result, Clinton pulled out of the race at the last minute. Marla Crider, who worked with Clinton in Arkansas and had an affair with him, describes women as being "literally mesmerised". "It was like flies to honey. I don't think there is any question Hillary was hurt," she says.

The decision to abort that early gubernatorial campaign was the first in a series of reversals and recoveries that have marked Clinton's career. David Maraniss, a Pulitzer prizewinning journalist and contributor to the documentary, believes it succeeds in revealing how Clinton's flawed nature both helped and hindered him. "People always try to separate the good from the bad in Clinton and say that, if he had not done certain things, he would have been a great president. But you can't do that. Those were his major characteristics," Maraniss told the Observer.

Clinton apparently deployed charisma of rock-star proportions, but with this came a sexual appetite that finally threatened his presidency when he faced impeachment for perjury over the Lewinsky affair in 1998. Wright tells the programme-makers she felt betrayed because the president had lied to her and "to a lot of people" about the affair. Barak Goodman, the award-winning producer who made the Clinton film for America's Public Broadcasting Service, points out that until now Wright has been extremely loth to speak about the incident. "She has been underground for many years because she was so close and so important to Clinton and felt very bad," he said.

Robert Reich, Clinton's labour secretary, also expresses his sense of shock about the Lewinsky affair. "He would not be so stupid as to jeopardise his whole presidency, I felt. That was not the man I knew."

Reich also reveals the rocky start to Clinton's presidency in 1993. "The atmosphere in the White House in that first year was chaos," he says. "Clinton wanted to be a part of everything."

The documentary, which was partly funded by US government grant and partly by donation, details early difficulties such as the scandal surrounding Clinton's affair with Gennifer Flowers, the sexual harassment suit brought by Arkansas state employee Paula Jones, and the devastating suicide of the Clintons' close friend, Vince Foster, at the time that the suspected Whitewater land fraud first case came to light.

During the period that the Republicans under Newt Gingrich blocked the national budget, Lewinsky began her internship at the White House.

"Monica Lewinsky gave him something that he needed at that time: to be adored," says Crider. When the affair became public, however, it fuelled the inquiry into Clinton's presidency being run by Kenneth Starr and led to the impeachment of a president for only the second time in US history.

According to the leading American journalist Jeff Toobin, who contributes to the documentary, the Lewinsky affair did not ultimately harm Clinton's image as much as predicted, .

"The legacy of this scandal favours Clinton more than his adversaries," he told the Observer. "More Americans think that it was a trivial waste of time than think that he got away with something unforgivable." Toobin puts this down in part to "a long-established pattern that the longer a president is out of office the more kindly the public starts to feel about them", but also to Clinton's resilience and to his "extraordinary political electricity".

"In comparison, too, both with [George] Bush, with his foreign misadventures, and with [Barack] Obama's economic problems, the boom years of Clinton's presidency start to look a lot better," added Toobin.

Tops at the Guardian

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