VENICE, Italy — Restricted travel, quarantine and positive COVID-19 tests meant that Majid Majidi's appearance at the Venice Film Festival for Iranian drama "Sun Children" (Khorshid) was an achievement in itself.

The film follows the story of Ali and his three friends on the streets of Tehran, as they try to find hidden treasure, digging a tunnel underneath a local charity school for street kids and child laborers. 

"It was difficult to come here," the director told Associated Press on Monday. "This was a whole new experience, like a new life." 

For 14-year-old lead Rouhollah Zamanisaghselou, in his first ever acting role, the coronavirus put a stop to his moment in the spotlight, after he tested positive and was unable to travel to Italy as planned.

"I told him when he was working hard digging in that tunnel that this film will become famous in the world and you will forget the pains. Then (when he tested positive for the virus) he told me: 'Mr. Majidi what should I do?' I was left behind with the pain."

Zamanisaghselou and many of the cast members were child laborers themselves when they were interviewed for the movie. Majidi explains that the casting process was extremely difficult but rich with talent.

"I actually interviewed two to three thousand kids and there was a lot of intelligence and potential kids in those groups," he said, adding that their backgrounds meant they had a lot of depth. 

"Because of the tough times they have been through, they are much more receptive and kind of older than their age and that's why they learn faster and better," Majidi said. "This was a huge encouragement and inspiration for them to become artists and actors, they couldn't even dream of such a thing before. This made them focus very closely and know that this is a very important moment."

Zamanisaghselou's Afghan co-star Shamila Shirzad, who has worked in Tehran since the age of 5, did make it to the festival and onto the red carpet Sunday. Majidi thinks that although she will have more hardship ahead, this is a great experience for her to "rediscover life and know that she can succeed if she studies and works hard. 

"She has had very difficult experiences in her life" he said. "But this kid fought back despite all those difficulties." 

"Now that she is here I can see how well she sees everything, and she knows that this is just temporary, and I see the worry in her eyes that she has to go back to her previous life, of course she is in a better situation now, with the help of some NGO she can focus on studying only, and doesn't have to work anymore."

And this is really the message of the movie. "I beg all people is to help the children discover their real treasures and build themselves and the society," Majidi said, who has noted there are an estimated 152 million children working to support their families.

"International organizations are waging a desperate fight to support these young people who are subjected to abuse and deprived of their human right to education. 'Sun Children' demonstrates the abilities and humanity of these children,'" Majid wrote in his director's statment.

"Sun Children" is one of 18 films competing for the Golden Lion at this year's Venice Film Festival.