The historian reveals hows Egypt's enemies exploited a country weakened by internal strife, travelling south to Sudan to examine the story of the forgotten Nubian kings, who ruled Egypt from their southern homeland for a century, even building their own pyramids to bury their monarchs. She then explores how the next group of invaders the Saites took the tradition of mummification to new extremes by preserving millions of animals, before Alexander the Great came to Egypt's rescue and founded the greatest city on Earth