You'd think a guy who went around invading other countries might be better known. And you'd think a historical biopic starring Ed Harris with a soundtrack by the legendary Joe Strummer would be easier to find.
And yet there's a good chance you've never heard of Walker – but this bloody and funny satire deserves your time.
Released in 1987, this biographical movie tells the story of William Walker, a real-life 19th century American "filibuster" who believed it was his destiny to invade various central American nations (for their own good, of course).
Walker isn't a typical period epic, however: it opens with a brutal massacre clearly influenced by the blood-spattered shootouts of director Sam Peckinpah, known for his tough westerns. And things get wilder from there. William Walker was not a very nice guy, and the film gets more and more unhinged as he spirals into madness.
Every biopic depends on its lead performance, and Ed Harris delivers an unforgettable turn as William Walker. As seen in The Rock, Harris is fantastic at playing someone completely convinced he's in the right, which excuses his immoral acts.
The chilling thing is that his moral conviction and zealous speeches seem to suck in everyone around him. There's something very relevant about a film where everyone is helpless to resist the power of a complete lunatic.
Wirral-born writer and director Alex Cox previously directed punk rock-inspired flicks Repo Man and Sid and Nancy. He also presented BBC TV series Moviedrome, introducing many young film fans to cult and classic movies that weren't easy to see in those days.
ForWalker, Cox wanted to go to the actual country where the historical events took place, so he took a crew of filmmakers and punk rockers to Nicaragua.
That was a pretty bold statement in the mid-1980s, when the country was torn by civil war between the socialist Sandinista government and right-wing guerrillas. Those guerrillas, the Contras, were funded and armed by the CIA. With this film, Cox explicitly connected the greed, exploitation and violence of the past with the present day.
Walker is an angry film, and explicitly political. It's also very funny. Cox deliberately works on various levels, from scathing satire to absurd slapstick. One great running joke involves a voiceover with Walker narrating his righteous deeds, grandly describing himself in the third person as if writing his own legend, contrasted with the grubby reality shown on the screen.
And as well as savagely skewering its real-life subject, Walker also takes aim at the genre of historical epics. Cox takes every opportunity to undermine the seriousness of period movies and hero-worshipping nature of biopics, through his use of black comedy, exaggerated gory shootouts and occasionally over-the-top performances.
Critics at the time derided the film's explicit argument, but that's the point. To draw a line to the present day, Cox sprinkles in anachronistic props and details (like a 19th century soldier drinking a modern bottle of Coke). By the time we get to the feverishly apocalyptic ending, Cox has exploded both contemporary politics and the entire biopic genre.
It's also worth mentioning the score by Joe Strummer of The Clash. Latin-flavoured and often juxtaposing jaunty music with onscreen violence, the score includes a number of haunting and lyrical themes.
Walker has benefited from a Blu-ray release, and there's a Criterion Blu-ray with lots of extras. Even today, though, Walker isn't available to stream or watch online in the UK, and pretty hard to find in the US.
Cox never made another studio film, going into indie movies and teaching. He claims that Walker's overt politics and punk attitude essentially ended his Hollywood career - but what a way to go out.
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