Few filmmakers have been so drawn to such delicate material where even slight shifts in tone or execution could mean the difference between a hit or a flop. That couldn’t be truer for Ang Lee’s new film, Life of Pi, a supreme balancing act for a filmmaker accustomed to working on tightropes.

Asked how he was doing, he exhaled:

“Better than I thought. I’ve been holding this anxiety for a long time. It’s an expensive movie,” says Lee. “It’s really like the irrational number of pi. For a long time it felt that way — not making sense.”

Life of Pi, in theaters now, has “all the no’s” of filmmaking: kid actors, live animals and oceans of water. It’s adapted from Yann Martel’s best-selling 2001 novel, in which a deadly shipwreck maroons a boy ( Suraj Sharma) on a lifeboat with a Bengal tiger.

Not only does filming such a tale involve considerable challenges, the story is ultimately a spiritual journey — and matters of God and faith are far from typical blockbuster fodder.

The Taiwan-born Lee is one of the few directors capable of corralling all the difficult elements. His imprimatur helps carry it, given that the cast is one of unknowns, digital creations and international actors.

“Why do I dare, a Chinese director, do Jane Austen when I still speak pigeon English?” Lee says, referring to his 1995 film Sense and Sensibility. “It’s still a leap of faith, you’re taking a risk. Every movie is unknown. If it’s known, then no studio would lose money.”

As for the future, Lee won’t contemplate his next film until he has seen through the present one.

He says: “I’m still surviving this one.”