Disney’s live-action/CGI hybrid film The One And Only Ivan is ramping up its pre-production and a new cast member has joined the project.

Ariana Greenblatt, who appears on Disney Channel’s Stuck in the Middle, has joined the cast of the film. Greenblatt will play one of the human characters who make up the live-action portion of the project.

Greenblatt joins a cast that includes Angelina Jolie who is voicing Stella the elephant, and The Florida Project star Brooklyn Prince who’s voicing Ruby a baby elephant, that Stella protects.

Written by Katherine Applegate and published by HarperCollins in 2011, the book centers on a silverback gorilla named Ivan who lives in a cage in a shopping mall along with an elephant named Stella and a stray dog called Bob. Ivan does not remember life before the mall, but when a baby elephant named Stella enters and Ivan finds himself taking care of her, he begins to rediscover his previous life and concocts a plan to take the baby elephant away from their abusive owner.

Thea Sharrock (Me Before You) is set to direct the film, with Brigham Young (Cinderella) producing the project.

There is no official release date for the film as of yet.