Anthony Arcaini has developed a piece he wrote for the Prince at the age of 12

As chance would have it, his ode was created in the tiny state where little Anthony (mother is German, father is Italian; born in the US) spent many holidays. His father Tonio, who once lived in Munich organises the Oktoberfest every October in the Principality. During preliminary discussions in 2008, Prince Albert asked the businessman to introduce him to his family.

Two weeks later the Arcainis and their four children had a private audience in the palace. And the then 12-year old Anthony composed his piano piece Monaco Fantastique in an instant for the prince.

Albert was fascinated by the musical performance and asked this up-and-coming Mozart: "Why don't you create an orchestral piece from that and then perform it with the Monte-Carlo Philharmonic Orchestra?" Anthony did not need to be asked twice. Over the next four years he wrote the music for the different instruments, adapted passages over and over again and allowed his work to grow with him. The fifth version of Monaco Fantastique was in good shape, he says confidently, and was available to the musicians. The deadline was three months before the concert.

In seven variations, Anthony uses his neo-classic music to explain what Monaco means to him: from Princess Grace and Prince Rainier III, the Oceanographic Museum, the palace gardens, the Grand Prix, the Casino and finally the fireworks festival. He doesn't want to give away any details, but promises a few catchy tunes and fanfarish melody.

Will this last version remain as the final work? His biggest role model, Gustav Mahler, constantly changed his pieces slightly, says the curly-headed composer: "It takes years until something is perfect," and “you change extremely quickly as a young composer."

As the members of the orchestra prepare for the performance on their own, Anthony spends hours every day absorbed in his work. There is no doubt that he is excited about the big evening, but at the same time he is amazingly serene. The better prepared he is, the better the orchestra will play, he quotes his professor as saying.

Anthony, who grew up in Florida with his three younger siblings and spent holidays in Monaco, has been studying conducting and composition for years at the University of Miami Frost School of Music. He is also studying privately for his high-school graduation, although at the moment the world premiere of his work has priority.

Four days before the big day he will take rehearsals with this world-ranking orchestra for the first time Will the musicians take the teenager seriously?

"I hope so," smiles Anthony, and again quotes his professor. "Age doesn't matter when you know what you want." He at least was looking forward to it, and after all this is not the first time he has conducted in public. He had his premiere at the age of 13, and last month gave the first performance of a hymn he composed in Tuscany.

The otherwise reserved Anthony is in his element when conducting and has no inhibitions about pointing out mistakes to the musicians and explaining his interpretation of a piece.

Meanwhile, his father wants to put the brakes on: "Two concerts a year is enough, I think," says Tonio Arcaini. "He already works 12 to 16 hours a day, but he should also enjoy his childhood." Opera houses the world over are keen to see what magic this young man can produce with his baton, enthusing about his precision.

In Monaco, Prince Albert will be sitting in the box. Monaco Fantastique is dedicated to him and his wife - and even the composer has not yet heard its orchestral version.

Aila Stöckmann/Ann Morris