Shadow of the Eagle is a 1932 Mascot film serial with John Wayne making his acting debut in serials. It’s about a mysterious pilot called the Eagle who threatens people with skywriting.
Buck Rogers is a Universal serial film based on the Buck Rogers comic strip. It starred Buster Crabbe (who had previously starred in two Flash Gordon serials) as the heroic Buck Rogers, Constance Moore as relatively seldom-seen romantic interest Wilma Deering, Jackie Moran as sidekick George “Buddy” Wade, and Anthony Warde as “super-racketeer” “Killer” Kane. In 1953, the 1939 movie serial was edited into this film.