The words “Uneasy lies the head that wears a crown” appear on the screen as soon as the lights go off. Usually, a motto borrowed from the Bard screams, “intellectually stimulating” but ends up setting the stage for another pretentious drama, stifled by its own self-consciousness. Stephen Frears’ “The Queen,” however, manages to live up to the expectations the quote establishes without falling victim to affected pomposity.

The documentary-like fictional film portrays the Royal Family’s reaction to Princess Diana’s death and the ensuing clash between modern ideas and traditional values. The restrained yet simmering conflict between Her Majesty Queen Elizabeth II and Prime Minister Tony Blair sheds new light on the intricacies of British politics while painting a candid, multi-layered portrait of one of the most enigmatic modern monarchs. The film pulls off this feat without unnecessary pompousness or exaggerated solemnity: As the Queen herself points out, that’s the way they do things in England — “quietly and with dignity.”

The movie redefines the meaning of “behind-the-scenes.” While Their Royal Highnesses are stalking a magnificent stag, the viewer is stalking them. In an insistent, voyeuristic manner, the camera takes the audience through bedroom doors, inside hunting jeeps, and ultimately, behind the façade of the Royal Family’s mythical image.

The movie alternates between documentary footage and fictional scenes. News broadcasts effectively drive the story and reflect the public’s response to the Royals’ discomfiting lack of emotion. Everyone is watching and being watched — many scenes show Blair and his staff or the Queen and her family in front of their respective televisions. This meta-viewership reminds the audience that “The Queen” mixes facts and speculations — the borderline between them is blurry — and underscores one of the movie’s themes: the power of media.

Newly-elected PM Tony Blair, played by Michael Sheen for the second time in his career, uses the media to “save [the Royal family] from themselves” (and increase his own popularity while he’s at it). Blair’s presence adds political flavor to the story, as his relationship with the Queen illustrates an often obscure aspect of the British state system: the monarch’s role in advising the government, and, in this case, vice versa.

The Royal Family is just like any other: They bicker in front of the TV, barbeque by the river (with questionable success) and say decidedly un-regal things, like The Queen Mother’s, “I don’t know. Nobody tells me anything!” James Cromwell as Prince Philip is deliciously obnoxious and obsessively proud, while Alex Jennings portrays Prince Charles as a sneaky, paranoid man willing to switch camps as soon as his team appears to be losing. When they’re together, however, it becomes obvious that the Royal Family members are not so different from everyone else. Yes, they argue about whether to take the private jet to Paris and their backyard is the size of a National Park, but in the end they’re just your (almost) average family. And such a portrait is, to say the least, refreshing.

The crown jewel of the movie, though, is Helen Mirren’s Oscar-worthy performance. She has already played a queen before, in the 2005 biographical drama “HM Elizabeth I,” and the extra practice was worth it. Mirren’s uncanny likeness to the current Queen of England aside, there’s not a single gesture she makes that isn’t royal. Her silence, as expressive as her words, is charged with quiet restraint. Her face allows the viewer to trace the intricate route of her struggle to come to terms with change. She portrays a woman whose world is turned upside down but whose strength of will allows her to overcome the shock of realizing that her stoicism may be out of date. On one hand, there’s the stern look, the resolute gait and that authority-heavy tone that prompts both dogs and humans to obey her orders without delay. On the other, the quiet suffering and pangs of doubt disperse the notion that the Queen is not a human being. She is, in fact, an extraordinary one, as Blair acknowledges; she might have taken a hard blow, “but she’s still, you know, the Queen.”

“All prime ministers go ga-ga for the Queen,” says Cherie Blair near the end of the movie. By the time the credits start rolling, you’ll know just why.