Based on Neko no Danshaku, Baron (literally "Baron, the Cat Baron") by Aoi HIIRAGI, the movie follows Muta (the fat cat in Whisper of the Heart) and Baron (also from Whisper) as they set out to rescue a young girl named Haru who has wandered into the world of cats.

Neko is a fantasy adventure story directed by Hiroyuki MORITA, with music by Yuuji NOMI (who also composed the music for Whisper of the Heart), and a script by Reiko YOSHIDA. It was released in theaters in Japan with Ghiblies Episode II on July 19, 2002 by Toho. It was produced by Toshio SUZUKI with Hayao MIYAZAKI as the Executive Producer.