What is the name of the Pokémon anime episode known for the 1997 flashing-lights incident?

The Pokémon episode known for the 1997 flashing-lights incident is Dennō Senshi Porygon.

The episode, whose title means “Computer Warrior Porygon,” was the 38th episode of the first Pokémon anime season. It was broadcast only once in Japan, on 16 December 1997. Rapid red and blue flashes during an explosion scene were linked to photosensitive seizures and other symptoms among viewers.

More than 600 people were taken to hospitals after the broadcast, and the incident became a major television and public-health story in Japan. The episode was removed from rotation and was not broadcast in other countries.

Despite the episode’s title, Pikachu’s attack produced the visually intense flash sequence, not Porygon. This is why Porygon is often incorrectly blamed in casual summaries. The incident also led to a roughly four-month hiatus for the anime and encouraged stricter precautions for flashing imagery in Japanese broadcasting.