The 10-year-old was making her big screen debut in the sci-fi thriller Knowing, which opened on Thursday.

Isabella's portfolio was given to producers by the Berwick branch of the Children's Performing Company of Australia, where she had been attending weekly drama lessons for about two years.

"Since Isabella was little, she's always been singing or dancing at home, her mother Rose Landolfi said. "She's always been a bit of a performer."

The Cranbourne girl has a small role in the film, which climbed to No. 1 at the US box office.

The race-against-time plot centres on an astrophysicist, played by Cage, who realises that a code in a 1959 time capsule holds the key to predicting future disasters.

Melbourne was the backdrop for the movie, giving locals the rare opportunity of spotting "homegrown" landmarks in a big American production.

About two weeks after auditioning, the call came through that Isabella had won the part.

"She filmed for four long days in the June school holidays last year. She'd get up at 4.30am and my husband Paul would take her to the film locations. She'd sometimes not come home until 8pm," Mrs Landolfi said.

"She was paid well but this was more about it being such an amazing experience for a child. She was fascinated about how they make a movie."

Isabella said she enjoyed her acting stint and was keen to do more.

"I really like to act. It was very different from doing a play as there were a lot more people," she said.

Mrs Landolfi said Isabella's brothers, Paul, 19, and John, 15, were rapt at the attention their little sister was getting, joking she would make more money than them.

The spotlight is set to remain on Isabella. Casey councillor Kevin Bradford, whose ward covers Cranbourne, is set to request permission at the next council meeting to use ward funds to pay for a civic reception in her honour.