Hollywood actor goes from Stargate to Edinburgh, and has Ugandan baby on way

How Johnny O'Callaghan is promoting his new show

Johnny O'Callaghan's story of an out-of-work actor who quit Hollywood in despair for Uganda only to adopt a child is a true story – about himself. And now it will be shown at the Edinburgh Festival.

O'Callaghan wrote the comedy-drama Who's Your Daddy? based on recent events in his life – "because I didn't want to do therapy" – and it played to packed houses in Los Angeles.

It came to the festival late, after another act dropped out, so it did not even make the official programme.

He moved from Ireland to Los Angeles after university, but beyond a role in Stargate Atlantis and a few bit parts, he struggled to realise his dreams of stardom. Following a tough breakup, a chance invite from a friend saw him go to help out at an orphanage in Uganda just three days later. "Nothing was going right," he said. "Staying wasn't the answer, and I felt fearless. It all happened so quickly. If I had thought it through, I wouldn't have gone." He was confronted with terrible poverty, had run-ins with child soldiers and faced the fallout of the simmering political tension that verged on civil war. "There were so many beautiful things, but there was so much desperation. Africa woke me up. This is a story of transformation," he said.

What he wasn't expecting was to establish such a strong connection with one of the children that he would adopt him. The show explores the trials of trying to become a Ugandan orphan's father, not only battling the bureaucracy in the country, but the reaction of those, including his family, back home.

He said when he wrote the story "it came out very quickly. I did a reading and people were moved, but they also laughed. So some friends talked about producing it as a play."

O'Callaghan, who is an American citizen, said he has enjoyed his first Edinburgh experience but was surprised by the competition of the shows: "It's like The Hunger Games, in a humorous way of course."