The Unseen Enemy in this wartime meller is Nick (Leo Carrillo), the outwardly effusive manager of a San Francisco waterfront café. To make enough money to ensure his daughter Gen's (Irene Hervey) entree into society, Nick sells his services to a gang of foreign spies, who then use Nick's establishment as a rendezvous point. The plan is to covertly send out a Japanese vessel for the purpose of raiding and destroying American merchant ships. The spies' secret code is hidden in the lyrics of a song called "Lydia", which the unwitting Gen performs on request day after day.

A truck convoy traveling the Burma Road is menaced by a group of smugglers.

Longshoreman Johnny Barnes is in love with Kitty Tracy, barmaid at her father's waterfront saloon, and he beats up Cassidy, a crooked politician who has been annoying her. Cassidy is murdered that night and Johnny is jailed for the crime. Kitty, her father Andy Tracy, and waterfront-priest Father Cameron believe Johnny is innocent but all evidence points to his guilt.

Story of test pilots at a school that trains new flyers.

The brash, opinionated owner of a nightclub manages to drive everybody crazy on a boat trip to Havana.

A sultry night club singer, a man who has also traveled to many exotic ports and a salesman meet aboard ship on the 45-mile trip from Hong Kong to Macao. The singer is quickly hired by an American expatriate who runs the biggest casino in Macao and has a thriving business in converting hot jewels into cash. Her new boss thinks one of her traveling companions is a cop. One is -- but not the one the boss suspects.