The Spook by Melissa Reeves, directed by Tom Healey. Design by Anna Borghesi, lighting by Richard Dinnen, composition and sound by David Franzke. With Alison Bell, Kevin Harrington, Margaret Mills, Denis Moore, Tony Nikolopoulos, Luke Ryan and Maria Theodorakis. Malthouse Theatre @ The Beckett until March 10.

Homebody/Kabul by Tony Kushner, directed by Chris Bendall. Designed by Peter Corrigan, lighting by Nick Merrylees, sound by Jethro Woodward. With Tyler Coppin, Ernie Gray, Shelly Lauman, Wahibe Moussa, Osamah Sami, Shahin Shafaei and Majid Shokor. Theatre@Risk at Trades Hall, until March 11.

Theatre is a many-splendoured thing, and much of it operates way outside the four walls of a building. After all, the biggest theatre at present, and certainly the deadliest, is the return season of Evil Brown Dictators with WMD, presently playing to packed houses in Washington. Astoundingly, it has the same plot as season one, although there are a couple of cast changes: one of the stars of last season, for example, retired to spend more time with his money, and of course the guys in black hats are, if not quite ambiguous, dizzyingly interchangeable.

Meanwhile, over in the Kodak Theatre in LA, Al Gore stepped forward to accept the Oscar for An Inconvenient Truth, and the boundary between showbiz and politics again dissolved into a terminal blur. Though, thinking over the traditional pageantry of power, it has to be said that such a division is often a mere courtesy, permitting politics the "seriousness" that theatre, being imagined, does not possess. PT Barnum himself stood for Congress, after all; former Oil Peter Garrett is a respectable Parliamentarian and Maxine McKew has announced her intention of standing against Howard in the next election. And so on.

The increasing public synonymity of celebrity and political power is a piquant symptom of the The Society of the Spectacle, which Guy Debord described in his influential 1967 work. He elaborates a capitalist world in which being is mediated and finally negated by representation, in which people are fatally alienated from their own experience. "The images detached from every aspect of life merge into a common stream in which the unity of that life can no longer be recovered," says Debord. "Fragmented views of reality regroup themselves into a new unity as a separate pseudoworld that can only be looked at. The specialization of images of the world evolves into a world of autonomized images where even the deceivers are deceived. The spectacle is a concrete inversion of life, an autonomous movement of the nonliving."

The spectacle, crucially, "is not a collection of images; it is a social relation between people that is mediated by images." (My italics). What Debord means in part is that the Western project of understanding the world has been cast primarily in the mode of one sense: sight. And that what we perceive - always, necessarily, at a distance - with our eyes has begun, not only to replace, but to obliterate the possibility of more fully sensual and connected ways of being in the world. As the Homebody says in Tony Kushner's extraordinary play, "All must be touched. All touch corrupts. All must be corrupted."

Homebody/Kabul and The Spook are both political works which seek to interrupt, in very different ways, the on-going theatre that constitutes the larger political world. Debord himself would no doubt consider all bourgeois theatre - of which both of these plays are examples - as fatally corrupted by its embeddedness in the very economic and social forms they seek to critique. But, given that, as Debord says, "consciousness of desire and desire for consciousness are the same project" and that the polar opposite of consciousness is the spectacle, one can argue that it is possible for the sensual realities of theatre, even bourgeois theatre, to lift the work out of the aura of undead commodity, and to shock us out of the alienated deathliness against which Debord argues so passionately.

I am tired of the political framing that places art simply at the service of one rhetoric or another, "left wing" or "right wing", as if that were all that is at stake: and here, however clumsily, I am attempting to signal how art might be most crucially political. When Debord claims that "the history of different ideologies is over", and that ideology - which crucially seeks to enslave and negate "real life" - now so saturates every social relationship that it is, effectively, without difference within itself, something in me leaps in recognition. And I look to art to spring this trap and, however contingently, to escape it. Both these plays, while overtly political in the sense in which the word is generally understood, strike me as political in this more profound way. They seek to escape, or at least to expose and question, the deadly spectacle that dominates our social discourse.

Homebody/Kabul was written by Tony Kushner before September 11 redrew global geopolitics. It famously opened in New York in December 2001, mere weeks after the terrorist attack on the Twin Towers. As a play which explores the West's ambivalent fascination with Afghanistan, mordantly predicting the violence that would ensue, it established Kushner's reputation as the prophetic child of American theatre. With this in mind, it is probably worth reflecting that one definition of "prophet" is he who sees the present clearly.

It is, indisputably, a demanding work: running for more than three and a half hours, it is a baggy monster of a play, switching between exhilarating flights of theatrical imagination and surprisingly heavy-handed scene making. Fortunately, the exhilaration by far outweighs the downside. It opens with an hour-long monologue by the Homebody (Jane Nolan), a London housewife whose reality is almost completely constituted by language. She reads from a historical guide book to Kabul, relating the city's history as, from its very beginning, a crossroad of imperial ambitions, of successive waves of migration, slaughter and war. It is, she says, the very burial place of Cain, "the inventor of murder". In between reading from the book, she speaks with seeming inconsequentiality about her life: her cold fish husband, her estranged daughter, her anti-depression tablets, her imagined erotic encounter with an Afghani trader in a London shop.

This monologue is breathtaking, and beautifully performed by Nolan: what seems at first to be a performance of overtheatrical brittleness becomes increasingly compelling, as the mask becomes a revelation of the Homebody's truths. She is, she says, an irritating person: excessive, prone to embarrassing gestures and linguistic flights, someone whose desires constantly overspill their narrow social constrictions. The Homebody is poised neurotically above herself, observing her own longing, hyper-articulate and yet helplessly at sea within her own words. The monologue ends with a recitation of a beautiful poem about Kabul by a Persian poet, a thrilling declaration of love. For as the Homebody says: "I love, love, love the world." And we believe she does. She simply doesn't know how to enact that love, or how that love might express itself in her closest relationships. It's as good a portrayal of emotional and social alienation as I have seen.

After this tour de force, the rest of the play can't but be a little anti-climactic. The next scene opens with the Homebody's family in Kabul. Her daughter Priscilla (Shelly Lauman) is hidden behind a curtain, her husband Milton (Ernie Gray) sits morosely on a bed, a Taliban official (Osamah Sami) sits sinisterly opposite, and a doctor (Shahin Shafaei) apologetically reports a litany of horrific injuries in almost completely opaque medical language. The Homebody, we realise, has flown to Kabul, and has been literally torn to pieces by an angry crowd for not wearing a burkha.

This introduces a lot of complex plotting, in which Milton stays in his hotel room, visited by what passes for the local British official, Quango Twistleton (Tyler Coppin). Twistleton, who owes his name to PG Wodehouse, is a junkie, trapped in Kabul as he is in his addiction, both loving and loathing it. He introduces Milton to opium and promptly falls in love with Priscilla. Priscilla, meanwhile, ventures out into the city, where she meets Khwaja Aziz Mondanabosh (Majid Shokor), a Tajik poet, who tells her that her mother is not dead, but has married a Muslim and no longer wishes to see her family. As Priscilla finds herself bewilderingly drawn into local political machinations, her father retreats further and further into his own bitterness, and the family's desperate history plays itself out.

The realities explored here are all contingent and hallucinatory: no one is sure what is true and what is not, and the texture of the writing forbids our sinking into a comfortable naturalism. Most of the time Kushner manages admirably not to burden his text with explanatory longeuers, but in the final few scenes the text begins to bog down a little, as if the playwright is giving in to the temptation to spell out its meaning. Kushner has the kind of clumsiness that is a characteristic of many brilliant writers - DH Lawrence, with his ability to switch within one paragraph from breathtaking genius to sheer awkward cloddishness springs to mind - a sense of utter writerly freedom, that refuses to pander to safe aesthetic rules, and which sometimes stumbles over its own boldness.

As should be clear already, this is a play that, above everything else, is about language itself: its capacities for deception and illusion, how it prevents communication as much as permitting it. Many dialogues are in Arabic or French, leaving English-speaking audiences, like the English-speaking characters on stage, guessing at its meanings; every character in it pushes against the limitations of language, or uses language to imprison others. Perhaps the most poignant joke is the poet who writes in Esperanto (a language that enchants him with its clumsiness); Esperanto being that utopic dream of a universal language which became the reality of a language that no one speaks. Yet for all this critique, Kushner weaves out of the dreams and fantasies of his characters a complex and communicable truth which is, perhaps, merely the truth of human pain.

Chris Bendall gives this play a most creditable production. Peter Corrigan's set shrinks the cavernous spaces of the Trades Hall ballroom to a curtained intimacy, with the audience two sides of a small stage. The cast and stage crew bring the props - beds, tables - on stage between scenes, so the play moves efficiently, if a tad predictably, between scenes. Performances are patchy: while no one is poor, some of the cast fails to attain the complexities the language demands, which is a tricky balance between heightened artifice and genuine feeling. Aside from Jane Nolan, that excellent actor Majid Shokor gives a rich and nuanced performance as the poet-guide Khwaja, and Tyler Coppin practically exudes the sour smell of loneliness as the ravaged Twistleton. And the whole is beautifully heightened by an evocative score by Jethro Woodward.

Melissa Reeves' play The Spook is a much lighter, and in some ways more deft, weaving together of international and domestic politics. Where Kushner is poetic, ambitious, unwieldy and astonishing, Reeves gives us the close-up realism of small-town politics. It's a solid piece of dramatic writing, with a surface sparkle opening to reveal undercurrents of tragedy. Like Kushner, Reeves is concerned with the real pain caused by political delusions and hallucinations: in this case, those of the Cold War, at the height of anti-Soviet paranoia.

Australia has quite a rich history of Russian paranoia, which in retrospect gains its true ludicrousness: the 19th century cannons pointing south into Bass Strait at Queenscliff were actually aimed at the Russians, while in the 1930s a secret army was raised to counter a tensely anticipated Bolshevik revolution. By the mid-60s, the Russian threat was Soviet and, although the Communist Party was not illegal here, ASIO planted spies - known colloquially as "sparrows" - into the Australian Communist Party.

Then, as now, Australian spying has an edge of the Keystone Cops. Just as ASIO sent spies a few years ago to a Teddy Bear's Picnic in Melbourne, in the 1960s they were busy reporting on subversive activities such as Mother's Clubs. Picking up on this edge, Reeves has based The Spook, already winner of the Louis Esson Prize for Drama and two AWGIES, on the true story of an ASIO agent who spied for 20 years on the South Bendigo branch of the Communist Party.

Martin Porter (Luke Ryan) is the archetypal true-blue Australian, recruited at 19 to serve his country by Alex (Denis Moore) during a football match. He's a decent boy: not overly bright, profoundly conventional and eager to serve his country. But, as is clear when the play opens and he is discovered reporting into a tape recorder as undercover agent "Iago", he is also fired by the romance of having a double life.

Under Alex's guidance he takes evening classes in Dialectical Materialism and attends weekly branch meetings which, far from being staffed by sinister types with bombs under their armpits, are tedious affairs dominated by discussions of factionalism and the continuing drop in sales of the Tribune. Anyone who has had anything to do with Left factional politics in Australia will recognise the set-up instantly: Reeves has a gift for nuance, and her portrayals are wickedly accurate.

In spying, Martin finds an outlet for his conflicting desires: on the one hand, he is ostracised in Bendigo for his radical views, long sideburns and leather jacket, while on the other he satisfies his craving for paternal approval, with Alex and the fatherland standing in for his dead father. The Communist Greek couple he befriends, Eli and George Tassekis (Maria Theodorakis and Tony Nikolopoulos) introduces him to a richer idea of life than the white-bread-and-butter conventions of regional Victoria, but even as he draws closer into their confidence, he faithfully reports their most damaging secrets to the authorities. And finally, the results are tragic, destroying the lives of his associates.

It's interesting to compare this play to Don's Party, David Williamson's rueful take on late-60s leftists. Although its focus is country Victoria, The Spook strikes me as a much less parochial work with far greater emotional reach. Reeves deftly weaves international politics into the domestic drama, with the Soviet crushing of the Prague Spring and the realities of Greece under the Colonels more than mere colourful background to her story. And it has considerable contemporary pertinence - a program note quotes an Age article which reports that ASIO has 20 per cent more staff now than at the height of the Cold War, and that since 2001 its budget has jumped from $69 million to $341 million this year. (Hello there, ASIO sparrow monitoring this blog!) Although this play looks like a comedy, its lightness of touch shouldn't fool you into thinking that's all it is.

Tom Healey has given it a huge production, in every sense, and it's hugely enjoyable. Anna Borghesi's ingeniously gorgeous set sprawls across the Merlyn, creating an interlocking flow of different domestic spaces in which walls lift to reveal sinisterly lit cloudscapes. Reeves is well served by an excellent cast: the performances are all good, catching the edge of caricature without becoming imprisoned by it. I especially admired Denis Moore in what could have been an unrewarding role as Alex, but which he infuses with a bitter pathos. However, in focusing - correctly, I think - on the comedy, Healey has missed some of the emotional depths that are also at work in the drama. This impacts especially in the second half, where some crucial moments are fudged. It struck me on the night I saw it as a matter of rhythm: perhaps, as it settles into its season, the production will heat up.

Both these plays, like all good theatre, make you reflect on the world's wider stages. In the flash and dazzle of the bigger spectacle, that may be a small thing; but in their affirmation of more humble and profound realities, it matters more than I can say.