Summary

Marie is fascinated by Henri Becquerel's discovery that uranium spontaneously emits energy or radiation. She makes this radiation the subject of her doctor's thesis and gets permission to work in a glassed-in studio storeroom in the School of Physics. There, despite poor conditions, Marie meticulously tests the radioactive properties of all known chemical elements. She uses those results to isolate two previously unknown elements -- polonium and radium.

In order to prove these elements exist -- because up to that point, they have not been seen in their pure state -- Marie struggles to determine the atomic weight of polonium and radium. Pierre comes to her aid, and the School of Medicine allows them to work in a dilapidated shed previously used for the dissection of corpses. It is a place...