Jonathan Bonfiglio is one of those writers who, I suspect, is never going to give us an easy time of it. You can't simply sit back and let Bonfiglio's work wash over you like a TV ad or a soap. His refreshingly intelligent work, which is essentially a combination of fascinating ideas and thought-provoking issues all wrapped up in a poetic style of dialogue, almost demands that you give it due consideration. In other words, you almost have to be a participant, rather than a mere observer.

Last year, I saw Bonfiglio's 'Human Remains', an examination of war and guilt constructed around the little-known fact that a handful of British men went to fight for the fascists in the Spanish Civil War. This new play, 'Pluto', involves issues on a larger and grander scale since the principle characters study the universe. But as in 'Human Remains', it's the relationships between the human characters which get put under the microscope – or should that be telescope?

Astronomer John Boötes is dying. He lives on a remote mountain in Chile where the skies are clear enough to study the heavens. He has – according to his wife at least - an unorthodox style in terms of his astronomical endeavours, and he's not approved of by the astronomical elite. His wife, Cass, left him shortly after the birth of their daughter Mira, who was born blind, and John was left to bring up the child on his own. But Cass has now returned at a time of crisis in space, in part because she thinks she's been 'summoned' by John.

Boötes' assistant Lau (ably played by Matt Addis) acts as a kind of narrator who develops the story for us and presents us with philosophical considerations to mull over. And there's a huge amount of it to digest. If I watched this play a thousand times, I'd be surprised if I could take on board all the issues it touches on.

Emily Agnew's thoughtful and sensitive direction rightly focuses on the poetic language which Bonfiglio's work employs. Though the script isn't exactly a tongue twister, it does require sympathetic delivery, and it gets exactly the right treatment here because all the actors have exceptionally fine, distinctive voices that work particularly well as an ensemble. And the clarity of the diction, helped by the proximity of the actors in a small theatre means we don't miss one word.

Matt Addis doesn't have an easy job since he's addressing the audience most of the time. But he skillfully keeps our attention by talking to each of us directly in turn, drawing us in and almost personalising the dialogue as if you were chatting with a friend.

Samantha Hopkins also has an unenviable task in portraying blindness as Mira, but copes with the challenge admirably. Since I'm unduly obsessive about believing in characters I often find disappointment particularly where accents or physical impairment are concerned. But Hopkins never betrayed her character, or gave the merest hint that she was other than blind. And if that wasn't enough, she also managed to characterize Mira as being stuck somewhere between childhood and adulthood, in a sense to show that her impairment and upbringing had restricted her development.

Bill Hutchens' Boötes is not exactly the most likeable of characters, but he arouses our sympathy nonetheless when his simmering bitterness, and sense of betrayal eventually burst out in justifiable rage against his wife. Moving as well as poignant.

The cast is completed by Ruth James as the estranged mother, Cass. Riddled with guilt for passing on defective genes to her daughter, and deserting her child and husband, Ms James presents a woman who one guesses would like to be forgiven or to at least explain, or even turn back the clock. Redemption, however, isn't on the agenda.

Though entirely professional and extremely watchable, my only reservation about the performances was whether there might have been a little more movement. There were times when the characters seemed a little static and where the judicious use of gestures in particular would have added to the characterisations.

It's unfortunate (in artistic terms at least) that safety requirements in some cases restrict creative freedom. Here, for example, I think the whole piece would have benefited from being much less brightly lit. But I think the main villain here was one of the emergency exit signs which seemed to be spilling over onto the acting area. It would have been better to have the actors almost in total darkness, but you can't always reconcile safety and creativity.

There's not much hope at the end of this play, and you're left feeling rather bleak, a little like a pointless speck of dust in a void bounded by billions of gigantic sparkling stars. Each character goes his/ her own way, never to meet again, one suspects. And there's a certain sadness throughout this piece and not just because of a major disaster in the skies which the characters witness, but are unable to prevent. It's more to do with people not really connecting, even though they might want to deep down inside. Something stops them - anger, timidity, blindness of one kind or another. In many ways the play is all about seeing and not seeing. It's also about identifying things and giving things labels, as the title of the piece implies (Pluto has recently been recategorised as a lump of rock or whatever, whereas previously it had been a planet. For most non-scientists, it still is).

Essentially, 'Pluto' is a tragedy. A tragedy which works on many different levels. Though Bonfiglio returns to explore some of the themes – guilt for example – that he's looked at before, 'Pluto' takes his writing to a new level of complexity, because it delves into more abstract concepts but still within a human framework. The overall effect is innovative and moving, thanks to a fine ensemble cast supported by enabling and intuitive direction. I wonder, though, if there's just too much to take in? An irresistible niggle for a reviewer, but not much more than that.

If any further proof were necessary that small-scale productions have big ideas and can make them work, 'Pluto' provides it. I don't suppose for one moment that it will be to everyone's taste, but it is an interesting and thought-provoking piece of theatre – drama with literary meat, if you like. Certainly worth taking a bite!

(Peter Brown)

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