When he was cast as Wolverine in the X-Men franchise, Hugh Jackman spent weeks researching wolves to inform his portrayal because he had no clue that there was an actual animal called a wolverine.
He recalled that director Brian Singer thought his performance was odd and asked him “Are you sort of walking funny, what’s going on?’ And I said, ‘I’ve been doing this thing with wolves,’ and he goes, ‘You know you’re not a wolf, right?'”.
When Singer informed him that he was supposed to a wolverine, “I said, ‘Well, there’s no such thing as a wolverine,'” Jackman says. Singer replied: “‘Go to the zoo, dude.’ I literally didn’t know it existed."