Sam Rockwell voices the creature who's discovering his artistic flair-and a yearning to be free.
"Actually, the first movie I ever saw was King Kong, and the second and the third King Kong remakes especially, have a kind of a take care of animals sentiment," Rockwell said.
Helen Mirren gives voice to Snickers, a poodle with attitude!
"Originally I wanted to play it with a really bad french accent, she was pretending to be very very French, she wasn't French at all," Mirren said.
Ivan's sidekick is a pooch named "Bob" who sounds just like Danny DeVito!
"I actually always wanted to play a dog. I like playing dogs, in fact, I act like a dog most of the time," DeVito joked.
"I wanted a love interest in the movie and when I heard that Helen was going to be the poodle, I've always had a crush on her," DeVito said. "Ivan has got this sweet, soft belly that I love curling up on."
"The One and Only Ivan" is streaming now on Disney Plus.