A movie serial in 12 chapters: The famous comic strip character is on a mission to protect a secret tunnel passage between China and India.
Tom Brown
as 'Smilin' Jack' Martin
Marjorie Lord
as Janet Thompson
Rose Hobart
as Trudy Muller, aka Fraulein von Teufel
Keye Luke
as Captain Wing
Edgar Barrier
as Tommy Thompson
Cyril Delevanti
as Mah Ling / Han Po, his double
Philip Ahn
as Wu Tan
Turhan Bey
as Kageyama [Chs. 1-5, 12-13]
Sidney Toler
as General Kai Ling [Chs. 1-5, 13]
Jay Novello
as Kushimi, infiltrator [Chs. 1-3, 12-13]
Rico De Montez
as Henchman Hito [Chs 1, 4, 12-13]
Nigel De Brulier
as The Lo-San [Chs. 2-3, 12-13]
