Devised and performed by Peter Finlay. Directed by Lloyd Jones. La Mama Theatre, Melbourne, to June 6; Bakehouse Theatre, Adelaide, June 30 to July 10.

Peter Finlay is an actor with an unnerving quality of violence. He can expose an unexpectedly louche physicality, which emerges with frightening force and suddenness from beneath a controlled and disciplined surface. When he is not acting well, this apparent contrast between surface and depth can result in a mannered performance close to parody, all surface skill over a core of emptiness. But in Projections 1, this potential flaw is transformed into a magnificent asset.

The premise is simple: Finlay has put together a collage of extracts from various movies, including Apocalypse Now, Silence of the Lambs, Stars Wars, A Few Good Men, Terminator and Pulp Fiction. Most of the extracts, so far as I could tell from my foggy memories of those movies, are accurate, but some - such as the Silence of the Lambs extract, in which Hannibal Lecter suddenly transforms into Carl Jung ruminating on the murderousness which exists at the bottom of our collective psyche - have been extended or turned.

It gives Finlay a chance to show off his considerable technical skills. He performs whole dialogues: captor and captive, interrogator and interrogated, a court scene, the famous conversation about hamburgers between John Travolta and Samuel L. Jackson in Pulp Fiction. His Apocalypse Now Redux, in particular, is really something to see. It occurred to me, watching it, that the real star of the show is Finlay's voice, a superbly agile instrument which makes those famous performances of Dennis Hopper, Marlon Brando and Martin Sheen eerily present in the theatre. But this somewhat underplays his physical skill, and how, despite how funny it often is, this performance goes beyond parody or mimicry.

Lloyd Jones has directed Finlay with great precision, and the two have ingeniously focused the individual performer even further by making Finlay control the minimal lights and props, and reducing all colours to a chiaroscuro of black and white. Much of the performance occurs in semi-darkness. Finlay's lighting consists of a torch and a desk lamp which are switched on and off and directed at will. He is a kind of theatrical one-man-band: he modulates his voice through plastic pipes and other simple objects, extending its range to incomprehensible radio gibberish, and explores all the sonic possibilities of his props: as drums, gunshots, ceiling fan. It's stunningly effective.

However, Projections 1 is much more than the extended party trick which it might have easily become. Since it is a single performer invoking all these voices and performances, the effect is very different from an exercise which splices together all these extracts together to make a film collage. When the violence explodes, it is shocking in a way that film cannot be: it is occurring right in front of you, barely ten feet away, and you are not quite confident that you are immune from its physical threat. And it is hard to escape the conviction that this is a particularly personal show. These are uneasy projections: as Prufrock says in Eliot's poem, it is "as if a magic lantern threw the nerves in patterns on a screen". Movies are, after all, the magic lanterns of our time, and their myths are influential in shaping our social and personal realities. Projections 1 is like being admitted into the hauntings of a singular consciousness: and what emerges is an abiding anxiety about masculinity and violence.

For all its concentration on popular movies, it is a surprisingly literary piece; Apocalypse Now harks back, for example, to Conrad and Eliot, the "hollow men" quoted by Kurtz. This literary play is picked up in the performance and reflects on the subtexts of all these different films. We live, after all, in an Americanised culture which is dominated by movies, and what Finlay is exposing is the murderousness at its heart: as Kurtz says, The horror, the horror. It is a particularly timely meditation as we quarrel over the rights and wrongs of our participation in the war on Iraq, and recoil from the violences which invasion and occupation always entail. The lines between reality and movie fiction are blurring further into hyperreality: the Terminator himself is the Governor of California and George W. Bush adopted the flak jacket and macho pose of the archetypal American Hero to announce victory over Iraq. I could have wished for more finessing of the script: the misogyny and homophobia which underlie these models of militarised masculinity are barely touched on. But that is a minor quibble.

Finlay finishes with a souped-up version of the ending of the Odyssey, and it is maybe here that this piece is most bleak. For in this story, when the Hero returns from war and adventuring, he is not welcomed home from exile: he enters his kingdom anonymously, like an assassin. And even before his kisses his wife, his first job is to murder all his rivals. It suggests that, from this constructed world of male violence, there is no coming home.