The real voyage of discovery, wrote Proust, is not to seek new landscapes but to find new eyes. Okay, it’s a cliche, a business-class motto that seems eroded by emigration and voyages of necessity. But can you still travel to lose yourself, find yourself, or at least to see things differently?

Such questions entered my head the other week while watching a Swedish icon of American film in an Irish play given a Polish production. I also wondered, in pleasant bewilderment, why Greta Garbo had a sex change.

The play was Frank McGuinness's fictionalised account of a real visit made by the "great gloomy Swede" to an Irish Big House in the late 1960s. On the page, Greta Garbo Came to Donegal is a fluent illustration of tangled national and sexual identities in textbook naturalistic style. Which is why an Irish spectator might be surprised when the performance halts for a minute and the entire cast dance the Valentina Twist , a Communist-era pop song dedicated to Valentina Tereshkova, the first woman in space. It was a gesture not so much lost in translation as spun gently out of orbit.

You have to go some distance to keep up withMcGuinnesswho,like many of our prominent playwrights, has had much of his work premiered abroad. Greta Garbo Came to Donegal opened in London in 2010 and its Polish translation just debuted at the Kontrapunkt festival in Szczecin, where a new collection of McGuinness's plays was also published.

I was fascinated at how the director, Anna Augustynowicz, had defused various problems (yet created others), and was deeply envious of her liberty-taking. An Irish premiere would have fretted as much as the London premiere did about finding a dead ringer for Garbo while observing the letter of the text.

The Polish version cut out stretches of dialogue and cast the magnificently hairless Maciej Wierzbicki (whose other stage credits include playing one of the leads in a play called Testosterone ) and nobody blinked. That approach made some overwrought symbols clang a little harder, but the production seized on the play's more subversive elements. In travelling, it had found itself.

It seemed similar from a Polish point of view. Here, an audience anxiously alert to how a country could be lost and retrieved in seemingly endless cycles watched the previous owners of the house now working for their English master. It made you reconsider the Valentina Twist and the gravity of Communism; nobody was dancing around the issue.

At a seminar devoted to McGuinness, the writer was compared in importance to Shakespeare and addressed as a distant kinsman. I was struck, though, by Augustynowicz's explanation of how her ensemble brought Ireland and Poland closer together, not by sketching any historical or geographical context, but by looking deeply and differently at themselves.

“We put the play in our own words and it crosses nationality and borders,” she said.

Now, I thought, you’re speaking our language.