Playwright Brian Friel dropped in on rehearsals for one of his most celebrated works at the theatre that premiered it four decades ago.
Philadelphia Here I Come! was first staged at Dublin's Gaiety in 1964, establishing the Co Tyrone author among the country's leading writers.
It returns to the theatre next month for a limited run, reuniting several cast members from the award-winning production of another Friel play, Dancing at Lughnasa.
Producer Noel Pearson said Friel, who is notoriously publicity shy, keeps a close eye on productions as they are transported from print to stage.
"Lots of academics said this was the one that changed Irish theatre because it was so unusual at the time, it was so original," Pearson said.
"He (Friel) pays a lot of attention. I don't think there are two days go by that we don't talk about it."
Philadelphia Here I Come! is set in 1960s rural Ireland and premiered in the Gaiety in 1964, catapulting Friel onto the international stage.
Pearson also worked on the Tony award-winning production of Dancing at Lughnasa in 1991 with a cast that included Brid Brennan, Gerry McSorley, Marion O'Dwyer and Barry McGovern.
They have been reunited for Philadelphia and on the first day of rehearsals McGovern, who plays schoolteacher Master Boyle, paid tribute to Friel.
"He is wonderful to work with in terms of notes and little things," he said.
"He wasn't hands on in (Lughnasa) rehearsals the way some authors can be, he was very quietly making observations.
"He worked through the director and he would occasionally talk to, certainly to me, about certain things.
"It's amazing how helpful he was."
During a career spanning around 40 years, Friel achieved critical acclaim and worldwide success with a raft of plays including Philadelphia, Here I Come! (1964), Aristocrats (1979), Translations (1980) and Dancing at Lughnasa (1990).
Friel received UCD's most prestigious honour, the Ulysses Medal, at a gala ceremony attended by poet Seamus Heaney at the university last year on Bloomsday, June 16.
He was also immortalised on the Gaiety walk of fame in September.
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