Series 2 Edit
Donal sits to the left-side of Irene with a gun in front of him. When Irene jokes about Thomas's desire to uphold his reputation Donald sarcastically retorts, saying "a reputation for not being scared of anything". As Thomas mocks the Paddise's fight over whether to accept or refuse the King's peace treaty, Donal rises from his chair, slowly picks up the gun, dragging it on the table and tells Thomas to stop smiling. When Thomas reveals that he knows Irene's identify, Donal points the revolver towards Thomas's head, asking Irene for permission to kill him. After she denies him the request, he reticently removes the gun.
During a meeting between Thomas and Campbell, Irene and Donal are also present. Thomas realises that the three of them are working together, which amuses him. Donal calls him an "arrogant bastard" and proposes for them to stop Thomas from mocking them for allying themselves with an agent of the crown. After Thomas is presented with the target of his mission, Donal tells him that refusing to carry out the assassination means death.
When Thomas exits the room, refusing to finish the mission, he reveals to Campbell that Donal is a spy for the Irregulars against the pro-treaty Paddies and is reporting every word back to them.
Henry is assassinated sometime in 1922 presumably by men working for Major Campbell. Proof of his death is sent to Thomas Shelby as part of his agreement to assassinate Henry Russell.
"There are other ways of carrying out this mission. Please allow me to put a bullet in this scum tinker's head." — Donal to Irene about Thomas Shelby