Werner Herzog: Radical Dreamer review - the visionary director's extraordinary career

“It’s an injustice of nature that I haven’t become an athlete and it’s an injustice of nature that we do not have wings,” says German director Werner Herzog, aged 81, sounding characteristically intense.

Who else, muses Wim Wenders, one of the many talking heads in Thomas von Steinaeker’s exhilarating documentary, has succeeded in “inventing” their own accent in a way that the whole world imitates and enjoys? Herzog is a “truly mythological creature” and has, he says, shaped the American perception of Germans like no one else. Though no one else is quite like Herzog.

His films – he’s the director of 20 feature films and 34 documentaries, as well as many operas - tend to be dream-like though he says he rarely dreams, but sometimes, after driving for 20 hours or so, sees his car “fill up with insects and butterflies.” In the Seventies he undertook the hallucinogenic, spectacularly strenuous, Amazon-jungle based projects Aguirre, the Wrath of God in 1972  - the film, remembers Patti Smith, "was like an exquisitely sour and sweet fruit you’d never tasted before” - and Fitzcarraldo (1982) both starring the violently deranged Klaus Kinski. “He’s contributed to our collective cosmic dream,” says Chloé Zhao.

In his later LA-based incarnation, he’s become best known to a younger generation for his documentaries such as Grizzly Man and Cave of Forgotten Dreams as well as for appearing on The Simpsons and starring in Jack Reacher and The Mandalorian. He once cooked his shoes and ate them. And he got shot at with an air rifle by a crazed fan while being interviewed by Mark Kermode in 2006, but refused to go to hospital, saying the abdominal wound wasn’t “significant”.

One of the more intriguing interviewees is Lucki Stipetić, Herzog’s half-brother, who has worked with him as producer on most of his films. He has a wonderfully deadpan, calm delivery, and, says Herzog, “has something in him that inspires confidence,” invaluable when 300 extras have gone on strike and are waiting to be paid in the Amazon jungle during the filming of Aguirre. He brought the money to Peru in a backpack, making “20 different stops, through the jungle, over the river, secured by a rope” and managed to save the project from financial disaster, as did Herzog’s other brother, Till.

As for Fitzcarraldo, It may be a familiar story but it's still a an extraordinary one. An epic, four years in the making, about a rubber baron determined to drag a steamship over a hill - “I really couldn’t imagine how that would work,” says Lucki mildly - it's hard to do justice to its madness.  There were two plane crashes, among other disasters. The technology was stone-age. Finding the right actor to play Fitzcarraldo was a drama in itself.

First Herzog wanted the “gruff, peasant-like” Warren Oates, but nothing came of it; then he liked the look of Houari Boumédiène, president of Algeria. Unsurprisingly, that wasn’t practicable. Jack Nicholson wanted five million dollars. “That wouldn’t have left much budget,” says Lucki, with magnificent understatement. Finally, Jason Robards took the role, much to everyone’s surprise as he’d never been abroad before, let alone to the jungle, with Mick Jagger as his side-kick. “No one had really discovered what a great actor he was,” says Herzog of Jagger. “He has a strange mad intensity and a fire within.” (Von Steinaeker uses footage of the two from Burden of Dreams, Les Blank’s brilliant 1982 documentary about the making of the movie.)

In the end Kinski, “screaming with happiness”, was brought on after Robards came down with a bad case of amoebic dysentery, went back to the US and never returned. They waited for him for a while but then Jagger had to leave to go on tour in Europe. Herzog didn’t replace him. Kinski, says cinematographer Thomas Mauch, “only cared about creating as much turmoil as he could,” though, says Herzog’s ex-wife Martje Grohmann, he learned his lines surprisingly efficiently.

Other intriguing scenes include Herzog mentoring young film film-makers in Lanzarote. His own mentor, legendary film critic Lotte Eisner, recognised Herzog's genius after seeing his Signs of Life, about a soldier who goes mad, in 1968. She told Fritz Lang that it had given her new hope for German cinema after the schmatzy rubbish, with "no real German people leading real lives," as Volker Schlöndorff puts it, that followed the Nazi era. In 1974 Herzog walked from Munich to Paris in order to save Eisner from dying, believing he could do so by “sheer will”.

His mutual love affair with America began in 1996 when he moved to LA with his wife Lena. “He was done with the smug narrow-mindedness and bureaucracy of the German system,” says Lucki, as well as with the fact that his films weren’t getting funded (and Lessons of Darkness, his meditative documentary about Kuwait after the first Gulf War, had a particularly harsh reception at the 1992 Berlinale). “I like to be in a place where you feel that things are wildly in gestation,” says Herzog.

But he’s never embraced Californian therapy culture. In his new memoir, Every Man for Himself and God Against All (vastly long, digressive and in need of an edit) he notes that “I have a deep aversion to too much introspection…I’d rather die than go to an analyst, because it’s my view that something fundamentally wrong happens there.”

In the last scene, he looks up at the waterfall in Sachrang, “the landscape of his soul”, the Bavarian village where he grew up with his brothers and mother after they were bombed out of Munich. Where is the waterfall's source? asks Lena. “I do not know and I do not want to know,” replies Herzog.

• BFI Southbank's retrospective season, Journey into the Unknown: The Films of Werner Herzog, runs throughout January
• More film reviews on theartsdesk