My Friend Dahmer

This story ends somewhere between a sculpture called Chromatic Fragments - Vortex To The Sky and another called Earth Flight. If you draw it one way, at least. Based on a version of a true story, My Friend Dahmer is a portrait of a serial killer as a young man. Wrapped in inherent inevitability, it's carried entirely in the stooped shoulders and blond fringe of Ross Lynch.

This is a sudden and astonishing arrival for an adult actor, Lynch a veteran of stage (as a member of pop group R5) and screen (a variety of children's television roles). It's potentially as improbable as the voice of Snufkin becoming that of Hannibal Lector. It's an incredible performance, one supported by a number of other excellent turns. This is a quiet, moody, tense exercise in naturalism, minimalism - and, as one might expect, foreshadowing.

Based on a book by John 'Derf' Backderf, this threads a difficult path around clues that we know lead to a monster. There's the temptation to place blame, to assign cause - as parents Joyce and Lionel, Dallas Roberts and a rarely better Anne Heche provide disquiet that nests, dwells, festers.

There are moments other than performance as well. The juxtapositions of early roadkill, a game of 20 questions, an act of erasure, demolition and experimentation, all part of an unfolding, one carried in the set of Lynch's shoulders. This is a film not only keenly observed, but keen to observe and to discuss the act of observation - a film that focuses on how things are seen. Concern is expressed that young Jeff spends too much time in his own company, but one glimpse in his own head is a moment of horror, wonder, and in a very specific way peace.

Writer/directer Marc Meyers' previous work has featured love stories, coincidences, family legacies, but all of them find focus, show talent, here. Film's an excellent place to show gaze, but there's real sublety in the distinctions Meyers draws here - even the friendly neighbourhood doctor, a minimal but key turn from Vincent Kartheiser, has a part to play. With a focus on adolescent hi-jinks, discovery and re-discovery, the act of depiction and acting and depiction on display here compel.

Though based on a book by someone who was there, characterisation often seems surprisingly fair. There's doubtless invention, but Alex Wolff's turn as Derf is subtler, fairer, more nuanced and even judgemental than might be thought. The story has been filmed before - Jeremy Renner another member of the 'has played Dahmer' club. Beaten to death in prison, dead in an ambulance on the way to hospital, Dahmer had celebrity presence - he's referenced in Demolition Man which puts him on similar name recognition territory to Taco Bell. As a film My Friend Dahmer walks a difficult line as a period piece, but does well - shades at once of Zodiac and Donnie Darko, it manages a credible but not improbable soundtrack, to reflect obsession without becoming obsessive.

With this kind of story it's hard to decide where to start, where to stop - over a brief window of the late 1970s, drawn from Derf's memoir, this is still a slice from life. Even in dialogue there is multiplicity - "it interests me, what's inside" - metatextuality and liminality abound, in frames and vistas and horizons, in small and technical detail - focus pulled to a microscope, sudden slides, "I don't know what happened," in balance. Adolescent sexuality, dissolving carcasses, bodies melting together. There are difficulties here, well explored in art though not in life. Even the decision as to the ending - the two pieces above art at a prison, art at a hospital. This story ends after a concert, in a way, but it's just another slice of before.

Seen on a freezing night at Glasgow's 2018 film festival, it wasn't only the weather that caused chills. With a naturalism of tone in its depiction of both lethality and high school it recalls the distance and poise of Gus Van Sant's Elephant, a story of a serial killer that avoids the lurid quasi-supernaturality of The Silence Of The Lambs. It's something different, off-set, odd, but all the more powerful for it.