Atom appears in the special "Tezuka Osamu ga Kieta?! 20 Seiki Saigo no Kaijiken" among other characters created by Osamu Tezuka. His cameo features a noted redesign with white gloves. The special provides no specific narrative details, character development, or background information for Atom.

Atom's core characteristics from the broader "Astro Boy" franchise include his creation as a 100,000-horsepower robot by Dr. Tenma, his seven powers (flight, super strength, multilingualism, analytical skills, headlight eyes, super hearing, hidden weapons, and moral discernment), and his thematic role exploring the coexistence of science and humanity. These established traits are not contextualized or expanded upon within this specific 2000 special.