Luke

Luke was a British citizen living and working in London in the mid-nineteenth century.

Luke was a laborer in a foundry owned by industrialist Matthew Killian. When installing heavy machinery, meant to replace some of the foundry's workers, Luke got his arm mangled. Following this incident, Killian fired Luke and his entire crew.

With the help of Peter Jespers, one of his colleagues, Luke managed to get work aboard the 616 train. One night in 1868, Killian boarded the train on his way to a business meeting in Wales, getting into a discussion with Angus Wolf. Luke, having never seen his employer, did not recognize him.

The following night, the Assassins Jacob and Evie Frye boarded the 616 train to investigate Matthew Killian's murder. After their investigation, they accused Luke's friend Peter, who readily confessed to the crime.

Reference

 * Assassin's Creed: Syndicate - The Dreadful Crimes