Thaddeus Valentine

Thaddeus Valentine is a fictitious historian of London in the book "Mortal Engines" by Philip Reeve.

Valentine has two daughters, Katherine Valentine and Hester Shaw. While Katherine's mother died soon after birth, Hester's mother married another man and raised her until Valentine ruthlessly murdered them, then slashed Hester's face with his sword, but because she was his daughter he could not bring himself to make sure she was dead, so she was able to escape. Ever after she waited for the day when she would avenge her parents' deaths. The reason for these murders was a piece of 'old tech', known as MEDUSA.

On an expedition to America, the 'dead continent', Valentine and Hester's mother/Valentine's lover (Pandora Shaw) found the plans of a weapon made by the 'ancients', called MEDUSA. However, several years later, Pandora returned to the Base where they had found the plans for the weapon, and after further exploration, found the Computer Brain of the weapon, and took it back with her. The Brain was useless, though, without the plans and codes from the last trip, now held by Valentine. Pandora, wanting to sell both the plans and the Computer to the Anti-Traction League so that they could rebuild it and destroy the Cities, called Valentine to her home, so they could sell the items together and split the profits. Valentine, who was also an agent for London, knew that if his City got the plans it would be unstopable. He killed Pandora and her husband, and seeing Hester had seen him, slashed wildly at her, ruining her face, but leaving her alive. After that, he took the plans and the artefact to London and helped the lord mayor, Magnus Crome, to recreate the weapon inside St. Paul's Cathedral.

Valentine comes into the plot one night in the 'Gut' when Tom Natsworthy saves his life from a veiled, knife-wielding girl (later to be known as Hester) attempting to take Valentine's life. After the girl falls off London, Valentine pushes Tom down after her. Unknown to Valetine, Hester and Tom had survived the fall. Later at Batmunkh Gompa, Valentine destroyed the 'Anti-Traction' League's airfleet and was confronted by Anna Fang. They fought furiously in the snow until Anna finally cut him to the quick - on his knees, leaving Valentine disarmed and exhausted, the very picture of defeat. However, just as she was about to finish him, Valentine's airship the "Thirteenth Floor Elevator", distractes her so that Valentine could grab her sword and plunge it through Anna's neck. Valentine later accidentally killed his daughter Katherine as she saved Hester's life. As she lay dying in his arms, he with the rest of London dissolved in an explosion of light as MEDUSA malfunctioned and destroyed itself.