Lo!

How huge, and in so many different and unexpected ways, has the internet grown since a team led by Leonard Kleinrock attempted in 1969, a few months after the first manned moon-landing, to send a message from their computer in UCLA to another in Stanford. It's a perfect subject for Werner Herzog's patient, humane, open-minded investigations of obscure wonders and the outer edges of human obsession, but his new documentary, Lo and Behold, Reveries of the Connected World, doesn't try to capture its entirety (there are scarcely any references to social media, sex, or shopping, for instance). Instead, it's divided into ten chapters -- 'The Early Days', 'The Glory of the Net', 'Artificial Intelligence', so forth -- woven from interviews with internet pioneers, victims of trolls, roboticists, medical researchers, scientists, entrepreneurs, hackers, and refugees.

Rather imposing a narrative commentary, Herzog mostly prefers to let his interviewees do most of the talking. And for the most part this works wonderfully well. Delighting in the aroma of old circuitry, Kleinrock gives a tour of the Spartan room (hey, I had a metal desk just like that when I worked at UCLA) in which that first message was sent (the connection broke while someone was typing the command Log, truncating a utilitarian instruction to the rapturous Lo). Danny Hillis recalls a time not so long ago when there were only two other Dannys on the internet ('And I knew both of them'), and flourishes a copy of the ARPANET directory from the 1970s, which lists the names and physical addresses of everyone who was then connected by the new technology, a small township long since swallowed by the exurbia of the current three billion users.

There's an engineer who admits love for the best of his football-playing robots, disquisitions on the networked intelligence of self-driving cars and how the idle moments of networked PCs are used to model the structures of medically useful biochemicals. But the documentary is at its most engaged when it shows how the networked world intersects with the raw stuff of human lives. There's a sober episode about an early example of the internet's dark side, where Herzog allows the Catsouras family, somberly arrayed, to explain how they were tormented by trolls who bombarded them with taunts about their dead daughter and photographs of her body after she was killed in a traffic accident. And he records without judgement the lives of people who believe that their health has been wrecked by civilisation's saturating buzz, and have found refuge in the shadow of a radio telescope sited in an area where electronic noise, from mobile phones to modern car engines, has been eliminated.

Two of the best moments come when Herzog chooses to speak up. He startles Elon Musk by volunteering for a one-way flight to Mars (now there's a documentary) and intrigues Musk and other internet enthusiasts with a question that's characteristically naive and profound: 'Could it be that the internet starts to dream of itself?' As impossible to imagine the thrilling and terrifying consequences of that as imagining the connected complexity of the happening world once was.