Zodiac Killer Project: experimental documentary expertly dissects the clichés of true crime

“If we’d made the film there would have been a car here, probably in that spot on the left,” Charlie Shackleton tells us in voiceover, introducing the concept of his new film Zodiac Killer Project, with the help of a landscape shot of a quiet rest-stop near Vallejo, California. It would have been the filming location for the first scene of a true-crime documentary that Shackleton planned to make, based on a book by former highway patrol cop Lyndon E. Lafferty, who believed he’d identified the Zodiac Killer, who murdered five people in the San Francisco Bay area in the late 1960s. Shackleton had the entire film mapped out when Lafferty’s family changed their minds and decided against granting him the rights.

In its place, Shackleton has produced a paean to this documentary never made, which channels creative frustration into something new. The director investigates a specific true-crime case, while providing meta-commentary on the trends that shape works in that wildly popular genre. It is a film that both structurally resembles what Shackleton -originally meant to make – presenting Lafferty’s story with some cinematic thrills – and a more formally experimental documentary that adroitly manages to both celebrate and critique the previously intended approach.

A basic similarity in outline between the film he imagined and the film he’s made allows Shackleton to somewhat circumnavigate the rights issue – by describing the planned film’s sequences, he can still wrestle with Lafferty’s account of hunting the Zodiac Killer. Of course, without the rights to the book, this can’t be done directly. Instead, the film nimbly picks out elements that are presented in other sources, verified and described by other people, falling back on the specifics of Lafferty’s telling in only the most dramatic and subjective moments – keeping the text’s inclusion in line with policies of fair use.

For the majority of the film, what we’re watching is 16mm footage captured by cinematographer Xenia Patricia. Barring a few exceptions, these shots pan across, or zoom in on, exterior or interior locations representing where the described action might have occurred. They are sparsely populated, mostly devoid of daily bustle, like abandoned film sets.

These are interspliced with cutaways to stagey re-enactments, so common to the true-crime doc – which, Shackleton explains, are referred to in the industry as ‘evocative B-roll’. He offers examples of what might have been included during each scene: footage of crime-scene tape being stretched out, or perhaps an interrogation lamp… “They’re always swinging,” Shackleton says.

During one moment when the camera is placed on the corner of a Vallejo intersection, Shackleton interrupts himself – “Oh, wait, this is amazing” – before a motorcycle does a wheelie across the screen. The incident somewhat recalls John Smith’s short The Girl Chewing Gum (1976), in which the filmmaker’s voice directly pre-empts the real-life occurrences on the screen. But in contrast to the exaggeration of the all-powerful voice of directorial authority in Smith’s film, this moment in Zodiac Killer Project highlights a continually shifting relationship between Shackleton’s voiceover and the images on screen – the film is still about asserting control but, for both Lafferty and Shackleton, the ability to do so is compromised.

We learn that Shackleton is narrating while sitting in a sound booth watching the same location footage as us. The ‘evocative B-roll’ cutaways then explicitly mimic his observations – as if they manifest from what he is saying. Our attention is continually drawn to the documentary’s construction and, by extension, to how similar things would have been true of the intended original film. As the narration describes the ways in which the genre tropes would have been deployed to embellish the tension of Lafferty’s story, we’re made aware of how that might be at odds with reality. It’s a highly effective method of exposing the audience to the moral quandaries inherent in the work, not allowing it to be consumed passively. And Shackleton manages to do it in an appealing, conspiratorial way, without seeming hectoring.

The result is Shackleton very much having his cake and eating it. He’s managed to describe the thrilling, possibly sensationalised film never made within the confines of an experimental documentary. What’s so impressive is the degree to which the amusing tone of his voiceover is consistently cut through by formal rigour and invention which expertly dissects the ethical implications of the genre.

► Zodiac Killer Project  is in UK cinemas 28 November.