Tatiana Mac, the American actress who plays Ana Steele in the parody musical version of E.L. James' best-selling erotic trilogy Fifty Shades Of Grey, unexpectedly has the bright, cheery disposition of a Disney character.

Rather than see this as a contradiction or barrier to the role, she embraces the possibilities in the apparent incongruity.

Speaking to The Straits Times in a telephone interview from California where she is based, she describes her portrayal of Steele as "a Disney princess meets Fifty Shades".

"Like if you put Ariel in a bizarre universe," she adds, referring to The Little Mermaid.

For instance, the first song she sings in 50 Shades! Musical Parody is the suggestive There's A Hole Inside Of Me, which she says is like Steele's version of the Little Mermaid classic Part Of Your World, "a song that defines Ana's purpose and dream".

"(Steele) is supposed to be relatable in her innocence and in how clumsy and awkward she is," says Mac, 27.

"She doesn't always have the right answer and isn't so put together, but I think what's interesting about 50 Shades is that everyone who reads it has his own interpretation of Ana in his head."

The off-Broadway production will be staged at the Capitol Theatre from Oct 18 to Oct 30. It is rated R18 (for audiences aged 18 years and older), for innuendo and a brief nude scene, according to Singapore promoter Seoul Bound Entertainment. Tickets are already on sale.

The parody relies on the original source material, about a literature major who has a chance encounter with a tycoon with a penchant for bondage.

James' books have sold more than 100 million copies worldwide and have been translated into 52 languages, while the 2015 film adaptation, starring Dakota Johnson and Jamie Dornan, earned more than US$500 million (S$673 million) at the global box office.

Mac admits that having played the role for more than a year now, she and her character have blurred into one.

"It's hard to tell where Ana ends and Tatiana begins sometimes," she says, chirpily.

"We're both very clumsy and awkward and laugh at inappropriate times."

It was her first major role after graduating from the University of California, Los Angeles, with a musical theatre degree.

She describes the production, which has had sold-out runs in New York and Las Vegas since 2014, as a "raunchy sex comedy". Through the narrative device of a book club, the show explores Steele and the titular character Christian Grey's trysts in some of the books most infamous scenes - including The Red Room, where he gives her a tour of his sex dungeon.

Mac describes the parody as a Gilbert and Sullivan-style comic opera take on the scene.

"We cover the entire laundry list of crazy sexual fetishes, some of which I never knew existed," she says. "I had to Google a couple of them."

After doing that scene, nothing shocked her anymore.

"There's something amusing about getting your leash stuck in your wig when you're also trying to do a dance and be spanked," she says of rehearsals for a highly choreographed portion of that scene.

"It becomes so ridiculous that you can't be shocked anymore."

Mac also believes that you do not have to read the book to enjoy the parody version. The production is chock-full of jokes and "hidden gems" that pay homage to famous musicals. There will even be certain segments of the show where the audience can play a part.

"My favourite thing about talking to the audience after the show is hearing the husbands say, 'My wife dragged me to this and I had no idea what it was going to be like, but that was pretty darn funny'," she says.

"So I'd say if we can get the husbands' seal of approval, for books they would never read, then I'd say you don't have to have read the book."