Mickey Rooney, who passed away earlier this week, had such an astonishingly long and varied career, from vaudeville to Broadway and from silent film to digital video, that it’s hard to sum up other than with banalities related to its very longevity. Rather than try to do any kind of justice to his entire career, I want to focus on a single, terrifyingly powerful performance that has stuck with me for years and, I suspect, will stick with me as long as I live, and that, to me, exemplifies something about his chosen profession.

That’s his role as Fugly Floom in “Babe: Pig in the City.” If you haven’t seen the film, stop what you’re doing right now and download it – but know what you’re getting into. This isn’t really a kids’ film; it’s like a cross between “Charlotte’s Web” and “Taxi Driver.” There are so many astonishing moments in the film – moments of terror, like Flealick the terrier’s near-death experience; of wincingly painful need, like the Pink Poodle’s shameless display for the dog catcher; and of deep pathos, like Thelonius the orangutan’s gratitude for the simple dignity of clothing. But a key anchor for the whole experience is Rooney’s performance as Floom, an aging, creepy clown.

The key to that performance is its sincerity. There’s not a moment in which Rooney mugs, or trades off his persona, not a moment in which he solicits our sympathy. He is completely inside this terrifyingly remote and strange character, a man who has become the clown, who is no longer performing because he is never not performing. The closest comparable I can come to the kind of pain I felt watching it is the experience of watching Emil Jannings in “The Blue Angel” – but there we have the consolation of narrative, of understanding how he became the pathetic character he is at the end, and our able, to some extent, to distance ourselves from him. I couldn’t do that with Rooney; he is, as Lear said of Poor Tom, “the thing itself” – not unaccommodated man, but social man, man repetitively performing the clownish role of being human, which is what, in this film, life in the city reduces us to.

Not every actor, approaching Lear’s four score years and as continuing more than a decade past it, would have such commitment to his art that he would undertake a role like Floom, put himself on the line like that, emotionally and artistically. Only a real artist would do that. Which is what Rooney was.