Chan Siu-hung is forced to become a prostitute, with the police following hot on her heels. Ching Chi-ko comes to her defence by claiming to be her husband. Chan is put up at Ching's roof hut named the 'Seventh Heaven' and the two gradually fall in love. Soon the war breaks out. Ching is drafted to do hard labour by the Japanese army. When the war is over, the crippled Ching returns and lies to Chan that he is already a married man, hoping to persvade Chan to marry someone else. Nonetheless, Chan's devotion overwhelms Ching.