In the final episode of Egypt, Jean-François Champollion has unlocked the ancient Egyptian hieroglyphs but, in doing so, faces opposition from the Church and a challenge to his own beliefs.
The programme begins in 1815, when everyone in Europe has been infected with a fascination for Ancient Egypt. The King of France buys - at huge cost - a relief, removed from the ceiling of the temple of Dendera in Egypt.
A number of experts believe this to be an ancient temple. There is much excitement about just how old it really is. If it was much older than 2,000 BC, it threatens the established chronology of the Bible.
Jean-François Champollion is invited to give an opinion by one of the King's aides, the Duc de Blacas. This is the first test of his ability to understand hieroglyphs.
Known as a free thinker, his presence makes the Church nervous. However, to everyone's surprise, Champollion declares, quite definitely, that the relief was made after the birth of Christ, due to the crude quality of its art and the existence of some hieroglyphs that spell the name of a Roman leader.
It is the first dramatic and very public demonstration of Champollion's understanding of the hieroglyphs.
In 1824 he is invited to Italy to see some of the world's greatest collections of Egyptian artefacts. While there, he discovers, to his delight, that he can read quite easily all the hieroglyphs he sees.
He is also able to decipher ancient lists of Egyptian Pharaohs and parts of the book of the dead, describing the journey of the Pharaoh through the afterlife.
He is the only person in the world who understands how to read hieroglyphs, but not everyone believes him. Jealous academics in Paris and elsewhere are waiting to disprove him.
Now Champollion is desperate to test his skill in the temples and tombs of Ancient Egypt but, as a poor country boy, cannot fund his own voyage.
The Church hears of Champollion's desire to travel to Egypt and they offer to support him on the condition that he never reveals any findings that contradict the teachings of the Church.
As a deeply religious and now desperate man, Champollion agrees. He assembles a combined Tuscan-French team and travels the length of Egypt, stopping in as many tombs and temples as he can.
They wonder at The Great Pyramids at Giza and then visit the the oldest pyramid in the world at Saqqara.
Here, Champollion discovers a tomb covered in ancient hieroglyphs. It gives him an amazing insight into the lives of the Ancient Egyptians, including their calendar.
It also tells him something incredible about the age of the world. The tomb belongs to a man called Menofre who was Royal hairdresser to a King called Djedkare – a King who lived during the fifth dynasty, one that predated Noah's Flood and, according to the Church and the Bible, could not have existed.
Champollion is awestruck by this knowledge and, several decades before Darwin, this was a discovery that threw into doubt the very date of creation.
But unlike Darwin, Champollion has to keep it to himself and it is a revelation that must go with him to his grave.
Finally, Champollion comes to The Valley of the Kings, where he spends months walking from tomb to tomb, reading the hieroglyphs.
Here, at last, he begins to understand the Ancient Egyptian religion, the motivation behind the construction of the pyramids, the temples and the tombs.
For the first time in over a thousand years, their system of belief and the true role of their Pharaoh become clear. Champollion has single-handedly unlocked the secrets of the lost civilisation of Ancient Egypt.