With Five Weeks in a Balloon, 20th Century-Fox hoped to cash on the success of the studio's earlier Jules Verne adaptation Journey to the Centre of the Earth (1959). The plot is set in motion when 19th-century explorer Fergusson (Sir Cedric Hardwicke) volunteers to head a balloon expedition to claim an otherwise unreachable chunk of African territory for the British Empire. Along for the ride are reporter Donald O'Shay (Red Buttons), absent-minded professor Sir Henry Vining (Richard Haydn), Vining's assistant Jacques (Fabian) and schoolmarm Susan Gale (Barbara Eden). Along the way, the little party acquires another passenger when they rescue native girl Makia (Barbara Luna) from a slave trader. Their many near-death experiences include a run-in with evil potentate Sheik Ageiba (Henry Daniell). Other reliable characters on hand include Peter Lorre, Herbert Marshall, Reginald Owen, Mike Mazurki, and, in a dual role, sneezemaster Billy Gilbert. Since no one could be expected to take this sort of fare seriously, Five Weeks in a Balloon is played tongue-in-cheek, peppered with such overripe dialogue as "You, sir, are a cad!" and "Kismet! We are doomed!"