In 1879, King Leopold II of Belgium launched an ambitious plan to plunder Africa's resources. The key to cracking open the continent, or so he thought, was its elephants - if only he could train them.

And so he commissioned the charismatic Irish adventurer Frederick Carter to ship four tamed Asian elephants from India to the East African coast, where they were marched inland towards Congo. The ultimate aim was to establish a training school for African elephants.

Following in the footsteps of the four elephants, Roberts pieces together the story of this long-forgotten expedition, in travels that take her to Belgium, Iraq, India, Tanzania and Congo.

The storytelling brings to life a compelling cast of historic characters and modern voices, from ivory dealers to Catholic nuns, set against rich descriptions of the landscapes travelled.

Roberts digs deep into historic records to reckon with our broken relationship with animals, revealing an extraordinary - and enduring - story of colonial greed, ineptitude, hypocrisy and folly.