US Consul in Singapore hires adventurer Frank Buck to take her to a remote jungle area where a plane carrying a US secret agent in possession of stolen Japanese plans for invading Malaya and Singapore has crash-landed.
The Japanese kidnap Buck's friend, the Sultan of Johore, who saw their fake archaeological excavation site. Gloria and Buck must figure out what the codename for the Japanese invasion - Seven Keys to Singapore - means and sabotage it.
Count Markoff offers 5 thousand dollars for an ebony cat (black panther) delivered by Friday. Frank Buck competes against his old mentor Dingo Larson, with whom he had a falling out. Meanwhile, Gloria is coping with a jewel thief at the Raffles Hotel.