"Eternal Party" is the last episode of the Toaru Kagaku no Railgun S anime adaptation, and the 48th episode of the Toaru Kagaku no Railgun animated series overall. The script was written by Yoshino Hiroyuki and directed and storyboarded by Konno Naoyuki. The episode's animation was co-directed by Tomioka Hiroshi, Kumagai Katsuhiro, Sato Marina, Sakai Satoshi, Komatsubara Sei, Kimoto Shigeki, Naoya Takashi, Ishii Tetsuya, Tanaka Yuichi, and Hiyamizu Yukie.