[7][N 2] Dr. Gray Thompson, an American missionary doctor, works alongside Dr. Sara Durand in a hospital he has built in a small hilltop Chinese village, while Japanese forces descend on China.

In the midst of aerial bombing attacks on the village, Dr. Thompson unselfishly helps the local residents, and especially the insurgent leader Chen-Ta, who loves nurse Siu-Mei, betrothed to Dr. Kim, a sympathetic Chinese/Korean doctor.

As appearing in China Sky, (main roles and screen credits identified):[9] Although Pearl Buck's novel had been optioned for film production in 1941, one nagging plotline held up actual work as screenwriters dealt with an unsympathetic anti-American Chinese character.

[11] During its lengthy and troubled rewrite as a succession of screenwriters, directors and production staff were assigned to the project, the studio considered a number of stars for feature roles including Claudette Colbert, Luise Rainer, Margo, Maureen O'Hara, Kim Hunter and Paul Henreid.

[10] The key role of the Japanese antagonist was played by Richard Loo whose Hollywood career in the war was accentuated by a large repertoire of sinister spies, enemy agents and military officers.

[13] Released at the end of World War II, China Sky did represent an attempt to portray the Chinese theatre of operations, but despite the game efforts of its stars, was relegated to "B" fare by its low production values.