During World War I, William entertained soldiers by arranging variety shows. After Moore stole silver from a general and had sex with the general's secretary, he was punished by being sent to the Forge. At the Forge facility in Dartmoor he was experimented on and turned into a vampire.
While in Dartmoor, William fell in love with another vampire named Mathew.
On 4 October 1915, William escaped from the Forge facility with 56 other test subjects. He and Mathew bought a theatre in Bristol where they lived for the next century. During this time, Nimrod was aware of their location, but didn't kill them because they did not harm humans.
In November 2001, after killing the vampires who inhabited the Dusk Casino, Nimrod went to a play at William's theatre. After the play, when all the actors had left, Nimrod shot William's heart with a crossbow, killing him and ending Project: Twilight. (PROSE: Project: Valhalla)