Dame Helen Mirren will voice one of the characters in an animated movie about a captive gorilla, reports Deadline.

The film in question is Disney's The One and Only Ivan, which is adapted from the bestselling 2012 children's book of the same name, written by Katherine Applegate and illustrated by Patricia Castelao.

It tells the story of Ivan, an easygoing silverback gorilla who lives in a cage at a suburban shopping mall. He'll be voiced by Oscar winner Sam Rockwell (Three Billboards Outside Ebbing, Missouri), while Angelina Jolie (who also co-produces) will voice Ivan's elephant friend Stella, and Brooklynn Prince, the 7-year-old breakout star of The Florida Project, will voice baby elephant Ruby.

Danny DeVito will also lend his talented tonsils to the film for an undisclosed role, though we bet it's Bob the stray dog who lives with Ivan. Dame Helen's role is more of a mystery: in the past, though, she's played an owl called Nyra in Legend of the Guardians: The Owls of Ga'Hoole, and the dragon-like Dean Abigail Hardscrabble in Monsters University, so we imagine it'll be a suitably regal animal.

Like Disney's recent reboots Beauty & The Beast and Jungle Book, the movie will be part animated, and part live action. Among those whose actual pretty faces we'll see are Bryan Cranston (Breaking Bad), Ramon Rodriguez (Iron Fist), Ariana Greenblatt (Stuck in the Middle), Indira Varma (Game of Thrones), and Eleanor Matsuura (Sherlock), though which parts they'll play hasn't been announced.

The One and Only Ivan went into production this week in London, helmed by Thea Sharrock, the director behind tearjerker Me Before You.

Have you read the book? Can you guess which role Dame Helen will be playing?