TV · 13 ep. Mighty Atom Season 2 · 3 months after Season 1 ep. 1 · Sat, Jun 6

Film Kitty's Studio Sequel to Koneko no Rakugaki

Film · 1 ep. Life of an Expert Swordsman ep. 1 · Tue, Apr 28

They belong to the season they started in, and air through this one.

TV · 13 ep. Mighty Atom Season 1 from Winter 1959