The secret lives of the worlds most mysterious cats are brought to light by advances in remote and low-light filming technology. In South Africa, we follow the nocturnal pursuits of the tiny black-footed cat that stakes its claim to the title of the world's deadliest, and in remotest Mongolia we reveal the rarely seen Pallas's cat, at home with her kittens - she hunts by looking like a rock. Finally, in South Africa, we uncover the secret of the serval that thrives amongst the futuristic landscape of Africa's biggest industrial complex. These are remarkable cats, with surprising lives in extraordinary places.

Scientists are studying cats in more detail than ever before, and what they are discovering is truly groundbreaking. Join the scientists in the field, testing new theories and challenging the conventional ideas about cats. New approaches and new technologies are allowing an intimate look at their previously hidden lives.

In Ruaha, Tanzania, lions form huge super prides in order to hunt giants. Amongst cats lions are unusual, the only one to live in groups. In numbers they find the strength and audacity to hunt the most formidable prey.