Alternate history is a perennial of science fiction and has even occasionally been used as a hook for journalistic political analysis, as in the long-ago Look magazine cover-story imagining of President John F. Kennedy's first thousand days. Much more recently, Sean Penn starred in the alt-history drama The Assassination of Richard Nixon (2004). That the British faux documentary Death of a President--conceived as a 2008 TV-news special about U.S. President George Bush's assassination nearly a year earlier and the sociopolitical fallout from that event-has been condemned sight unseen by politicians and pundits from James Pinkerton to Hillary Clinton is understandable and completely predictable: They can't not comment, so when they do, they have to play to their audiences. None of them seriously believes that this work of fiction will really make someone take a potshot at the president, and anyway, the attempt on President Ronald Reagan's life came out of a crazy guy's fascination with Jodie Foster, so you may as well decry movies starring blonde former child actresses.

In fact, it's hard to imagine anyone without a political agenda who can walk away from this serious, sober and impeccably respectful film and get agitated about it on its merits. Mimicking the look and tone of documentaries done in the wake of tragic deaths from JFK to Princess Diana, director Gabriel Range--a former documentary filmmaker for the ever-staid BBC and others--and his producer and co-screenwriter, the Cambridge-educated former documentary producer Simon Finch, provide all the formal gravitas one would expect. It's 2008, nearly a year after President Bush was shot by a sniper outside the Chicago Sheraton on Oct. 19, 2007, dying shortly thereafter. Forgoing a narrator, though with occasional intertitles setting time and place, the mock documentary rounds up the usual talking heads to recreate what happened: the Secret Service agent heading the presidential detail that day (Brian Boland), the FBI special agent in charge of the investigation (Michael Reilly Burke), a Washington Post reporter (Jay Patterson), a Bush speechwriter who was there (Becky Ann Baker), and others. The filmmakers achieve their what-if world through ingenious CGI-manipulated and artfully juxtaposed real news footage and newly shot "surveillance videos" and such.

The mesmerizing true-to-life result is actually less about George Bush, who's presented as a more multifaceted human being than in probably more real-world accounts, but the post-murder environment. Vice President Dick Cheney is sworn in as the 44th president of the United States, and pushes forward the Patriot Act 3, permanently granting law enforcement unprecedented surveillance powers on U.S. citizens and others. He also toys with an attack on Syria, which reputedly stonewalls an investigation into the leading suspect, a Syrian-American named Jamal Abu Zikri (Malik Bader), who is eventually convicted on questionable forensic and circumstantial evidence. The documentary, however, also offers another, much more likely suspect, along with well-placed red herrings throughout.

The actors portraying the interviewed experts are by and large remarkably convincing, and the overall film so much so that it at times becomes unexpectedly moving. Seeing Bush speechwriter Eleanor Drake choking up despite her best efforts to remain composed on camera crystallizes the human element that reminds us all, ideologues and idealists alike, that no one person has the power that a system has. The nation simply kept moving after Nixon's resignation; it would do the same here. The real shot we should all take is to create a system we all can live with.