Sword Art Online: Progressive – Aria of a Starless Night is a 2021 Japanese animated science fiction action adventure film based on the Sword Art Online: Progressive light novels written by Reki Kawahara and illustrated by abec, which serve as an expanded retelling of Sword Art Online's Aincrad storyline. The film is produced by A-1 Pictures and directed by Ayako Kōno, while featuring character designs by Kento Toya and music by Yuki Kajiura. This is the second film, after Sword Art Online the Movie: Ordinal Scale, of the Sword Art Online anime series. The film depicts the story of Asuna's initial struggle to cope with being trapped in Sword Art Online along with her friend Mito, the first encounter between her and Kirito, and general in-depth coverage of events that occurred on Aincrad's first floor that were either skimmed over or skipped entirely in the original series. The film premiered in Japan on October 30, 2021.