Working in Venice, that is, for one of her cinematic heroes on the set of the new romantic comedy "Casanova" and playing a character, Francesca, who is "just fantastic."
The delightful Miller is unabashed in her enthusiasm. And why not? At 23, she is clearly enjoying herself and proving too, that's she's got the talent to match the belief that has been shown in her by some top filmmakers including director Lasse Hallstrom on "Casanova" who says, quite simply: "She's a film star, make no mistake. And a pleasure to work with."
In the film, the legendary Casanova (Ledger) is about to meet his match with an alluring Venetian beauty, Francesca (Miller), who does that one thing he never thought possible: refuse him. Through a series of clever disguises and scheming ruses, he manages to get ever closer to Francesca. But he is playing the most dangerous game he has ever encountered - one that will risk not only his life and reputation, but his only chance at true passion.
So far, Miller has played a small but undoubtedly eye catching role in the British crime movie "Layer Cake," opposite Daniel Craig, and won acclaim for her performance as a needy, insecure young American woman who falls prey to the predatory "Alfie" (Jude Law) in Charles Shyer's remake of the sixties classic.
And if that wasn't enough, she has also recently made her West End stage debut in "As You Like It." But playing the feisty Francesca opposite Heath Ledger in the title role of Casanova has proved to be one of the most vivid experiences of her career so far.
"It's fantastic. Lasse is one of my heroes and he made one of the best films I've ever seen - My Life as a Dog," she says. "It's one of my top five films of all time. And you can tell by his films that he is a great guy -and he is. He is just very generous and very calm and very focused and knows exactly what he wants. So it's been a great experience."
Filming on location in Venice has proved a challenge, but a rewarding one. "Venice which is like Disneyland for adults," she notes. "And you've got hordes of people coming in and out. I would think logistically if you are a producer it has to be your nightmare working here. But if you ever needed something to get you into a role this would be it. I've loved shooting here even though there have been elements of it that are really tricky - it floods a lot for a start."
Sienna has also enjoyed her working relationship with her leading man, Heath Ledger. The two of them became the production's on set jokers. "Heath is such a great guy, he is the most fantastically laid back fun person to work with on set," she says. "He is completely stupid on set which I love."
Opening soon across the Philippines, "Casanova" is distributed by Buena Vista International through Columbia Pictures.