A mill-owner's ambitious daughter almost ruins her husband's political career.

Poor physics student Marie is studying at the Sorbonne in 1890s Paris. One of the few women studying in her field, Marie encounters skepticism concerning her abilities, but is eventually offered a research placement in Pierre Curie's lab. The scientists soon fall in love and embark on a shared quest to extract, from a particular type of rock, a new chemical element they have named radium. However, their research puts them on the brink of professional failure.