Following a suspicious earthquake and a series of signals, Professor Norton leads an expedition with Crash Corrigan and reporter Diana Crompton to the likely source, the undersea city of Atlantis. There they become embroiled in a civil war between Sharad and Unha Khan, with Khan looking to conquer Atlantis and then destroy the upper world with earthquakes. Ray 'Crash' Corrigan ... Crash Corrigan Lois Wilde ... Diana Compton Monte Blue ... Unga Khan William Farnum ... Sharad Boothe Howard ... Ditmar Raymond Hatton ... Gasspon C. Montague Shaw ... Prof. Norton Lee Van Atta ... Billy Norton Screenplay by John Rathmell, Maurice Geraghty and Oliver Drake Directed by B Reeves Eason and Joseph Kane DVD 5: PAL: Black White