True Heaven (1929)

"A story of heart beats and air bombs, and of the supreme test of love."

Phillip Gresson is in the employ of the British secret service, while heroine Judith is a spy for the Enemy. Hoping to gain possession of the usual Secret Plans, Judith pretends to be in love with Phillip. Only after nursing the seriously wounded Phillip back to health does Judith come to the realization that she genuinely loves him.