Dr Julia Ravey and Dr Ella Hubber both have a love of science, but it turns out there’s a lot they don’t know about some of the leading women at the front of the inventing game. In Unstoppable, Dr Julia and Dr Ella tell each other the hidden, world-shaping stories of the engineers, innovators and inventors they wish they’d known about when they were starting out as scientists. This week, the story of an Indian chemist whose work laid the foundations to save thousands of lives.

In a lab in 1950s Kolkata, Asima Chatterjee laboriously extracts chemicals from the Indian snakeroot plant. She knows she’ll have to send the products away – she doesn’t have the money or resources to analyse them in India. But the tireless and uncompromising chemist perseveres, and her work paved the way for modern-day chemotherapy treatments.

Asima grew up in a time when it was uncommon for women in India to have an education, but went on to become a hugely influential figure in her field whose work is still repurposed and cited today. Dr Ella and Dr Julia take us through her inspirational journey, joined by Professor Sivapriya Kirubakaran and Dr Sarah O’Connor.

Presenters: Dr Ella Hubber and Dr Julia Ravey Producers: Ella Hubber and Julia Ravey Assistant producer: Sophie Ormiston Production Coordinator: Elisabeth Tuohy Editor: Holly Squire