IMDb has not listed Susan Sarandon as appearing in this film but...

Susan Sarandon is not listed on the credits for the movie Mr Popper’s Penguins but she was seen visiting the set during filming. I reckon Susan is doing some work experience so she can direct her ping pong documentary of her club/bar SPiN New York. Otherwise, Susan may be performing an uncredited role in the movie. Susan was also sitting in on a Hitchcock film lecture at Uni California a few days earlier, with many other students who wouldn't stop gawking at her. I love how she believes that there is no age barrier to learning something new or different.

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