I missed the opening night of The Seed. From other reviews I've read, this was probably a good thing: sometimes it strikes me that press night is probably the worst time to review anything. Instead, I attended a matinee a week or so after the opening, and saw a work that had been run-in in front of audiences and was probably closer to the director's intention. I walked out with one big, nagging question. What's wrong, I thought, with making things up?

Tony Martin, Sara Gleeson and Max Gillies in The Seed. Photo: Jeff Busby

The Seed is a fictionalised autobiographical play by Sydney actor/writer Kate Mulvany (as the program explains, it's based on her own family history, reinforced by interviews from Vietnam veterans). Before this production, directed by at the Fairfax Studio by Hayloft artistic director Anne-Louise Sarks in her MTC debut, it had two successful outings at Belvoir, in which Mulvany played the role that is presumably based on herself.

The play itself shows that Mulvany is a writer of considerable talent, with a good line in tough, sparky dialogue and an actor's understanding of the stage. But its framing and structure are clumsy: The Seed feels chained by its roots in biography and social issue. It's a text struggling to take imaginative flight, a play that wants to be a play but is bogged down somewhere in a no man's land between documentary and fiction. This is reinforced by the meta-fictional figure of Rose, who carries a tape recorder as part of her mission to note down her family history, presumably so she can write the play we are watching, and flicks it on whenever her father or grandfather threatens to launch into a speech.

The story follows Rose (Sara Gleeson, in the role originally played by Mulvany), as she travels to Nottingham with her father Danny (Tony Martin) to visit her tyrannical grandfather Brian (Max Gillies). Danny is a Vietnam vet, whose family has been devastated by the on-going effects of Agent Orange; aside from Danny's continuing health problems, Rose's childhood was blighted by congenital cancer, and she is infertile as a result. Brian is, or claims to be, a hard man of the IRA, responsible for bombings all over England, and Danny's thuggish brothers have made a fortune with criminal trades in drugs and guns. Danny is the weakest link, the disloyal brother who ran away, and his homecoming is full of spikes and uncomfortable revelations.

There are, in fact, strong echoes of Harold Pinter's early masterpiece The Homecoming here: the set-up - prodigal son returns home from the new world with his wife (or, in this case daughter) - is very similar. Sometimes the dialogue hints at Pinter's black, surreal humour, and there's the same unsettling psychological switch when Rose, like Pinter's Ruth, announces her intention to stay with the Nottingham family, espousing their criminality. Here the switch only lasts a moment, and is, unlike Pinter's, made explicable by the psychological realism that underpins the play.

But these Pinteresque echoes were perhaps why I kept wondering why Mulvany hadn't simply written a play, rather than clinging to the work's biographical seed.  If she had followed these subtextual instincts, she might have written something deeply interesting. It could have rid her of the extraneous framing devices, and especially of the continuing monologue that punctuates the action, a childhood memory of Rose's, which has the adjectival diction of a short story rather than drama.

More importantly, she would have been primarily obedient to the imaginative imperatives of the play, rather than to extraneous considerations such as historical or social fact. Paradoxically, to do so might have brought the themes Mulvany explores - betrayal, secrecy, government lies, the scars of war - more powerfully to the stage, as action rather than explication. Admittedly, it would go against one of the strong conventions that underpins so much contemporary drama and literature: the idea that something is based on "a true story". This is a sales point as much as anything, but it does sometimes make me wonder if imagination is illegal.

But this is a lot of "what if". All these speculations stem from a feeling that this is a play articulated when it is still half-formed, a yolk-wet embryo struggling from the imaginative egg. And perhaps this quality is exposed by Anne-Louise Sarks's production, which gives the writing nowhere to hide. The Fairfax Studio is one of the most problematic spaces in Melbourne - very few productions work entirely here, and only those designed with the difficulties of the space in mind - and The Seed illustrates why.

This play would have benefited from a small, intense playing area (as seems to have been the case in Sydney): here it is performed on an empty stage scattered with props and furniture, and its dynamics and relationships are too often lost. Like the play, the direction suffered from a confused conception: it seemed to be directed as a stripped back in-the-round production, perhaps intended to highlight the meta-fictional aspects of the script. But this approach demands a kind of intimacy that the Fairfax doesn't offer.

Max Gillies's portrayal of the patriarch Brian was by the far the best performance on the afternoon I went, his bluster and boastfulness gradually wearing thin as his stories are exposed for the sad fantasies they are. I couldn't work out what Sara Gleeson was doing, but thought that had as much to do with her role as her performance: her character is most often a catalyst for the conflict between the father and son, rather than a presence in herself. Tony Martin in the central role of Danny was an exercise in surface acting, the rhetorical gesture substituting for something more real: there wasn't one moment in which I felt the physical danger of his anger. Mostly his character seemed weak, whereas the dialogue suggests a man with a hidden, perhaps unrealised, strength.

In short, this production had problems all the way through. What saves it from direness is in fact the strengths of the script, and in particular the dialogue; but these strengths make it the more disappointing.

The Seed, by Kate Mulvany, directed by Anne-Louise Sarks. Set and costumes by Christina Smith, lighting by Matt Scott, composition and sound design by Jethro Woodward. With Max Gillies, Sara Gleeson and Tony Martin. Melbourne Theatre Company, Fairfax Studio, Arts Centre Melbourne, until April 4.