Hoffman, who voiced all of the characters in the new children's book by his friend, author Holly Goldberg Sloan, says his granddaughter Daisy Jo believed she was born to play the titular marsupial.
"When she found out I was going to do the voices, she says, 'But I'm the perfect Appleblossom,' " Hoffman tells PEOPLE. "She wanted to do Appleblossom, so when she was told that I was doing it, she said, 'Oh, he always gets the best parts.' "
The Oscar winner, 78, turned out to be the perfect fit to narrate the heartwarming tale of a brood of baby possums who must learn how to navigate a world full of cars, humans and "dreaded hairies" (a.k.a. dogs).
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It's a rare children's book that has the power to change a reader's perspective – especially an adult reader – but Appleblossom the Possum seems to have done just that for Hoffman.
After recording the audiobook, the actor was invited by the author to pose for the above photo with a real, live possum named Mary.
"It was a rare occasion of having in life a prejudice that is quickly dissolved. It doesn't happen that often. I had seen possums in my life … and I always found them quite ugly," Hoffman explains. "But [after reading] the book and meeting a real possum, I decided that they're quite beautiful."
In fact, "if it wasn't for my wife's objection, I'd probably have one as a pet," he continues. "It was easy to fall in love with Mary – she was very shy but very sweet. I'm glad that Holly wrote this because not only is she good at it, but I think she's reversed an unwarranted prejudice against possums … It's a wonderful book."
Hoffman, who says he couldn't "live without reading," is currently revisiting an old classic: Charles Dickens' A Tale of Two Cities.
"I don't think people in general realize that [reading] is one of the best ways to socialize. You can actually have dinner, you can go out and have a drink with Charles Dickens, even though he's not there anymore. You can socialize with these great writers."
His only wish?
"I think if I had three wishes from God, one of them for me would be to be able to read much faster."