While working in a Whitechapel factory with his brother Buck, Dooley became involved in an altercation with Tom Coulton, who was beating his brother. Coulton turned his attention to Dooley after he interfered in the fight, causing Dooley to be knocked unconscious.
When he woke up, the foreman of the factory had been killed with Dooley's work knife, and the boy was briefly suspected in the investigation. Eventually, Jacob and Evie Frye traced the murder back to Coulton, clearing Dooley's name.
Dooley later encountered the Assassins again when they were investigating the disappearance of one of his friends Arthur Conan Doyle. Dooley had no information about his whereabouts, but did share details on Doyle's way of hiding information, allowing the Frye twins to continue their investigation.