Despite a distant history of bloodshed between the U.S. and Great Britain, the two English-speaking countries have been joined together in a Special Relationship, built on shared diplomatic, cultural, and political aims, for more than 50 years. While the phrase was first coined by British Prime Minister Winston Churchill in 1946, the Special Relationship may have truly reached its apex with the friendship between Bill Clinton and Tony Blair.

That partnership is what HBO’s biopic The Special Relationship, directed by Richard Loncraine ( The Gathering Storm), revolves around: the diplomatic and personal ties between Clinton and Blair during the 1990s and how their friendship was tested by a number of obstacles, such as Kosovo, the Troubles in Northern Ireland, and the Monica Lewinsky scandal, the latter of which shined a glaring spotlight on the private lives of public figures.

About the scene in which Bill Clinton confesses his affair to Hillary, Hope Davis said: “It was very, very hard to shoot that. As a person, and a woman, and a wife, you don’t really want to invade that space.”

The Special Relationship—which airs this Saturday on HBO and will be released theatrically in the U.K.—arrives at a particularly important time within British politics, following the election that saw Gordon Brown step down from the Labour Party and concede victory to Conservative Party candidate David Cameron after he successfully created a coalition with the Liberal Democrats. Brown’s defeat ended a 13-year Labour government, though the seeds for the party’s defeat can be seen in the faltering of Blair years earlier, with the partnership he forged with Clinton’s successor, George W. Bush. Brown’s removal from 10 Downing Street brings an end to an era of center-left politics in Britain.

• Dennis Quaid on Playing Bill Clinton “There definitely is a pendulum in politics, isn’t there?” said Dennis Quaid, who plays Bill Clinton in the film, lounging on a couch at a suite at the Four Seasons Hotel in Los Angeles. “The way the world was back then, all the social estates had fallen and the world was really being remade at that time. The two of them joining together felt they were a force in remaking it.”

Ultimately, however, the pendulum swung the other way.

The film, which is set between Blair’s election in 1997 and the 2000 U.S. elections, is part of writer Peter Morgan’s so-called Blair Trilogy, one that began with 2003’s The Deal and continued with the Academy Award-nominated feature film The Queen, which itself depicted the contentious relationship between Tony Blair (Michael Sheen) and Queen Elizabeth II (Helen Mirren).

But The Special Relationship captures a number of liaisons, both political and personal, swirling around couples Tony and Cherie Blair and Bill and Hilary Clinton. Quaid packed on 35 pounds to play Clinton, while Hope Davis was brought in to play first lady Hillary Clinton after Julianne Moore dropped out two weeks before principal photography was slated to begin.

“We’ve all gone through the same sea change together, being a little suspicious of her and what her role is and why she stays with this person,” said Davis of Hillary Clinton. “Now we understand that she is a public servant and she wants to serve the country. She has an approval rating of 77 percent right now. She’s an incredible human being, clearly.”

Clinton’s legacy has been tainted because of his involvement with White House intern Lewinsky, and The Special Relationship tracks how the friendship shifted between Clinton and Blair following the very public discussion of the illicit affair he had with Lewinsky—and depicts the conversation where Bill tells Hillary of the extramarital trysts.

“There was quite a discussion about the confessional scene in the bedroom,” recalled Loncraine. “We shot a lot more than we used… The Hillary side of it was very much a concern because we knew that we were dealing with the private lives of people… I wanted to show that they cared about each other.”

“They both alluded to what happened in that room in their books,” said Davis. “But, of course, we don’t exactly know. No one wanted to invade their privacy to that degree. We wanted to be respectful of all four of these people. So, in the end, they decided to kind of leave most of that out, which I think was really smart. It was very, very hard to shoot that. As a person, and a woman, and a wife, you don’t really want to invade that space. It was bad enough that they had to go through it in all in public.”

As for Sheen, he stepped back into the wingtips to play Blair, his third time in the role. He’s joined by his co-star from The Queen, Helen McCrory ( Harry Potter), as anti-monarchist Cherie Blair, a barrister who suddenly found herself the wife of the PM and was “unfairly judged by the British media,” according to McCrory. (Sheen and McCrory, who is the wife of British actor Damian Lewis, have been friends for years and started a production company when they graduated from drama school.)

“In a weird way, the more I have played [Blair], the less I can say about him,” said Sheen, looking every bit as polished as his subject. “He seems to be a man who constantly talks about wanting to do the best thing for his country, for his party, and it’s selfless what he talks about. But a lot of people would say he is ruthlessly ambitious and totally driven by self-interest in terms of his career. He is a man who, in the flesh, has a kind of relaxation about him and he is very good with people, and yet he became the most hated politician in the country.”

“One of Blair’s mistakes was picking up the relationship with George Bush where his old one with Bill Clinton left off. They were two very, very different people,” said Davis.

Blair’s mistakes comprise much of the action of The Special Relationship, signifying a very different Blair than we saw in The Queen, where he was portrayed as confident and forward-thinking, a do-gooder who had ideas of progress and reform. While the first two films in the series were directed by Stephen Frears ( Dirty Pretty Things), he declined to direct the final installment in the Blair trilogy. Morgan himself intended then to direct The Special Relationship, which would have marked his directorial debut, but he later stepped down and was replaced by Loncraine, who stepped in to direct shortly before production began.

“I consider myself a storyteller,” said Loncraine. “That’s why my rise to mediocrity, as I refer to my career, has been a bit checkered. I’ve jumped around a lot... Sometimes it’s paid off; sometimes I’ve made a bit of an ass of myself. But I’ve always tried to do something that was different.”

While The Special Relationship might seem like a fairly straightforward story, it’s actually a complex series of political maneuvers, bruised egos, and glad-handing as the action swirls around four highly intelligent individuals, bound together by bonds both matrimonial and political. “It was a hard film to edit,” said Loncraine, who admitted that the editing process and reshoots took a while longer than he anticipated. “To get the relationships right, there was a lot of discussing and creative arguing, I hope, about how much of the women should be in there and what should their roles be.”

While the political plot revolves around such politically charged events as the Kosovo war, the Northern Ireland peace talks, and the Whitewater and Lewinsky hearings, much of the action actually unfolds in restaurants, kitchens, and laundry rooms as Bill and Tony reflect with each other and with Hillary and Cherie, bringing the political sphere into the domestic situations of these two political couples.

It helps to make the film more accessible to the audience, according to Loncraine. “You don’t have to be a political major to actually understand this film.”

While there had been talk of a fourth Blair film from screenwriter Morgan, Sheen said The Special Relationship already touches upon the end of Blair’s government.

“I think this is Blair’s downfall,” said Sheen. “This is that film. I have always felt this is the film about Iraq. There is no mention of Iraq—we don’t get to that point in the film—but this is what this film is about and that is what made it so exciting in a way, doing a film which is all about what brought Blair down eventually, and what led to the Iraq war, and why things are the way they are [today]. The seeds of all that are in here and I find that in a way more dramatic and tragic and chilling.”

“If we only knew what was coming,” said Davis, of the pivotal scene between Clinton and Blair, set in a kitchen, as Gore concedes the 2000 elections. “If we only knew how very scary that moment was… The war in Iraq never would have happened, everything would be different. We’d have wind farms all over the place. The oil spill… I mean, who knows how different the world would have been? It’s just so very sad to contemplate.”

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Jace Lacob is the writer/editor of Televisionary, a website devoted to television news, criticism, and interviews. Jace resides in Los Angeles. He is a contributor to several entertainment websites and can be found on Twitter and Facebook.