Kate Barlow was a young teacher living by Green Lake 100 years ago. Everyone flocked to her school, young and old, because she was such a good teacher.

Trout Walker, who expected to get whatever he wanted, was annoyed when he was rejected by Kate. Kate fell in love instead with the steady, kind, intelligent, and hard-working onion seller named Sam. She always bought extra onions to give to his old donkey, Mary Lou, and made a deal to give Sam jars of her spiced peach preserves if he did repairs on the schoolhouse.

Sam happened to be Black, and when the two were seen kissing, the racist townsfolk became upset. Trout was especially angered and gathered together a mob. The sheriff told Kate that if she kissed him, he would spare Sam. She slapped the sheriff instead.

Kate and Sam tried to escape the mob by rowing across Green Lake, but Trout and his companions overtook them in a motorboat. They shot and killed Sam. Mary Lou the donkey was also killed.

These events changed Kate. She was no longer the sweet, loving person that she used to be. She got revenge by killing the sheriff. Then, putting on red lipstick, she gave him the kiss he wanted. Because of this, she earned the nickname "Kissing Kate Barlow." She became an outlaw and a fugitive.

The text is clear that Kate was not born an evil person. She hardened and turned bad because of the way the townspeople treated Sam.