Historically, Ash Ketchum’s Pikachu, the lovable yellow Pokémon, has not spoken a human language.

Pikachu had always communicated with Ash, his beloved trainer, by saying his own name over and over again in different intonations.

So when “Pokémon the Movie: I Choose You!” debuted in the U.S. last week, the audience was understandably shocked when a particularly emotional scene featured Pikachu speaking to Ash in English.

In a (likely illegally filmed) video of the scene posted to Twitter, audience members gasp loudly when they hear Pikachu profess his devotion to Ash using English words. “What the fuck?” one moviegoer says. “No!” another yells.

Pokémon fans in Japan first heard Pikachu’s expanded vocabulary in July, when the Japanese-language version of the movie debuted there.

American audiences seemed particularly unsettled by the scene:

The most disrespected I’ve felt in 2017 is when I heard Pikachu speak English — Jordynne Grace (@JordynneGrace) November 17, 2017

SO. UM. I GUESS PIKACHU SPEAKS ENGLISH IN THE NEW POKÉMON MOVIE? THIS IS AN ABOMINATION. GOTTA THROW THE WHOLE THEATER AWAY NOW. — Grace Ragan (@grace_kathryn_) November 16, 2017

Which is worse. Pikachu speaking English, or the fact that it wasn't Danny DeVito's voice. — julian yeo 🥡 (dm29) It's a Horse-Kinda Holiday (@judacris) November 15, 2017

The scene between Ash and the English-speaking Pikachu may have been part of a dream sequence in Ash’s mind, according to The Guardian, which spoke to Kate Bristol, the English voice actor for Pikachu.

Bristol told the newspaper that she attempted to mimic Ikue Otani, the Japanese voice actor for Pikachu, in her own performance of the famous Pokémon.

“I know a lot of people might think it’s out of the ordinary for Pikachu to speak English. It’s definitely out of the ordinary,” Bristol told The Guardian. “It was hilarious being in the theater with the rest of the cast and hearing the audience’s reaction as a huge collective ‘What?’ rose up.”

For some Pokémon, speaking human language is nothing out of the ordinary. Meowth, one of the TV series’ antagonists, often hurled threats and insults at Ash and his friends. Other Pokémon that can communicate with humans in their language include Gastly, Slowking and Mewtwo, according to the Pokémon online encyclopedia Bulbapedia.

“Pokémon,” the video game, card game and subsequent film and TV series, has attracted a cult-like following since it was introduced as a pair of Game Boy video games in the late ’90s.

Pikachu, with his round beady eyes, cherry cheeks and adorable squeaky voice, has become a key figure of the brand as Ash Ketchum’s sidekick. It’s no wonder some fans in the U.S. have found themselves emotionally attached to the way the furry yellow Pokémon says “Piiiiiiiiikachu.”