In a classic 1991 episode of The Simpsons, Lisa is distraught to learn that her inspirational substitute teacher, Mr. Bergstrom, is leaving her.

With his train ready to leave the station, Mr. Bergstrom writes Lisa a note. “Whenever you feel like you’re alone, and there’s nobody you can rely on, this is all you need to know,” he says. Lisa opens the note as Mr. Bergstrom’s train disappears into the distance. It reads, “You are Lisa Simpson.”

Yeardley Smith, who’s been voicing 8-year-old Lisa since 1987, was in her twenties when the episode was made. She was flown to New York to record her lines opposite Dustin Hoffman, who voiced Mr. Bergstrom. It was a career highlight.

But she didn’t quite comprehend that note.

“I remember reading that and going, that’s it? That’s all you have for my girl? I so didn’t get it. Fucking hell. That’s all she has to go on?! I was like, I don’t know what the fuck you’re talking about. I don’t know what this means.”

Smith sounds almost exactly like Lisa—which can make it feel weird, and more than a bit wrong, to hear her cuss. “Oh, my holy fuck,” she says at the mention of an episode from 2000 that envisages Lisa Simpson succeeding Donald Trump as president. “Yes! Oh! If only. Oh my god. Ugh.”

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