Four bells! That is the secret signal, By the time the Czar's hated inspector walks into the classroom, the forbidden Polish books have been hidden, When he asks to hear the dreaded lesson, the teacher cannot take a chance. She calls on Marya. Marya is a remarkable child. She grows up to be Marie Curie, a remarkable woman. In Paris, Marie explores new ideas in science. Then she and her husband Pierre Curie make one of the most important discovery that helps to change the world we live in. Here is the story of one of the greatest woman who ever lived.