Wicked: For Good goes beyond Broadway musical Wizard of Oz

When Universal Pictures split its musical adaptation of Wicked into two films, the move was derided by some critics as a cynical -- if spectacularly successful -- money grab.

But with Wicked: For Good out in theaters around the world this week, its stars and filmmakers say the decision has freed them up to expand the Wizard of Oz prequel far beyond the Broadway musical on which it is based.

The result includes an expanded new take on one of the most famous moments in movie history, with the arrival in Oz of a young girl from Kansas called Dorothy.

And the additional running time also allows for two brand new songs -- one of which, ‘The Girl in the Bubble,’ sees Ariana Grande's popular, pink-clad heroine Glinda confront her unlikely dark past.

"It happens in the wings of the Broadway show. You see the before and after moments," Grande said at a recent press conference.

But in the second film, we see "beneath the bubbly, shiny, perfect exterior" and "spend some more time with that darkness," she added.

‘Wicked: For Good’ picks up several years after the first ‘Wicked,’ with Cynthia Erivo's Elphaba now living as a rebel in exile, unfairly smeared by all as an evil witch.

Glinda, meanwhile, has become the poster girl of the Wizard's regime -- a position that brings her privilege and popularity, but also awakens guilt and shame, stemming from her childhood.

"She's gotten everything she's always dreamt of, and yet has never been more alone," explained Grande.

The pop singer already received a best supporting actress Oscar nomination for the first "Wicked." Universal is expected to pour resources into seeing that she wins the statuette this time around, and she is already the bookmakers' favourite.

Erivo is also a strong best actress hopeful, according to awards prediction site Gold Derby, and has a new song, "There's No Place Like Home."