Daddo stars alongside Toby Francis and Stefanie Caccamo in a story about a Dublin busker on the verge of giving up who meets a piano-playing Czech immigrant, who reminds him to dream.

The Broadway show is based on the 2007 film of the same name, with music that has won an Academy Award, Grammy Award, Olivier Award and a Tony Award.

"It's an intimate story about two very specific people, which has affected millions all over the world because it's so truthfully told," director Richard Carrol said.

"There's no more universal language than the language of music."

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Daddo will also be part of a free Merrigong "Talking Point" following a performance on Saturday afternoon, July 27, in the foyer of IPAC.

He will be in conversation with the musical director of the production, Victoria Falconer, and will discuss turning movies into musicals.

The Merrigong season will also include a post-show Q&A on July 25, an audio description/captioned performance on July 27, and a tactile tour also on July 27.

Earlier this year Daddo's own romantic life was making news after he and wife Alison Brahe opened up on a 10-part podcast on the ups and downs (and infidelity) in a 30-year marriage.

"What I discovered about myself is that I had a very childish need to be liked, which is why I probably ended up in the business because you get such a rush if people want you and all that sort of stuff," he told Studio 10 in May.

"we dove into therapy, we dove into our issues," said Brahe. "We were so young, we were engaged after two and a half months, then we threw ourselves into another country [the US].

"There was so much that we did in those early years that we just didn't settle, so it just blew apart."

Tickets for Once are on sale via www.merrigong.com.au

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