O'Malley is a bodyguard on Nassau on New Providence Island.
During the events of Black Sails: Season 1 Episode 4 IV. played by Karl Thaning
O'Malley tells Mr. Scott that the Andromache has arrived. When Eleanor Guthrie and Mr. Scott leave the room where she is having a meeting, she indicates to Mr. Scott that O'Malley and a few other men are ready to take Captain Bryson hostage if she gives the order. Bryson walks out of the room and tells Eleanor she will have her cannons and then calls Hayes to leave. While O'Malley is on watch to make sure Bryson is bringing the cannons, Mr. Scott takes his rifle away and knocks him unconscious.
During the events of Black Sails: Season 1 Episode 5 V. played by Karl Thaning
Eleanor tells O'Malley that no one has seen Mr. Scott and she thinks he might have left with Bryson. She goes into her office and later O'Malley tells Eleanor that something is going on outside. She goes outside and hears as Richard Guthrie tells the crowd that he is a fugitive and Bryson took all the goods except the few in the warehouse and that Eleanor is in charge of giving to those who are owed credit. Captain Lilywhite riles up a crowd of people and accuses the Guthrie's of stealing their money. One of the pirates sees Eleanor and charges at her, but is stopped by Captain Benjamin Hornigold. Hornigold suggests to Eleanor that she makes some announcement that debts will be paid. She refuses and tells O'Malley to bring Captain Naft and his quartermaster Mr. Walker, Captain Lawrence, Mr. Harrison, and Frasier to her.
During the events of Black Sails: Season 1 Episode 6 VI. played by Karl Thaning
The Ranger crew are ambushed by Eleanor's men and as O'Malley goes to kill Hamund, Anne Bonny stops him and stabs Hamund to death. He later tells Eleanor that the deed is done.
During the events of Black Sails: Season 1 Episode 7 VII. played by Karl Thaning
O'Malley calls to Eleanor and tells her that Mr. Scott refuses to leave.
During the events of Black Sails: Season 1 Episode 8 VIII. played by Karl Thaning
O'Malley runs into the room and brings Eleanor and the rest of the Consortium outside. Captain Charles Vane walks up with his crew and tells Eleanor that they need to talk.
During the events of Black Sails: Season 2 Episode 1 IX. played by Karl Thaning
Eleanor brings O'Malley with her to speak with Vane at the fort. Jenks then brings Eleanor to see Vane.
During the events of Black Sails: Season 2 Episode 2 X. played by Karl Thaning
O'Malley enters the room while Eleanor and Meeks are talking and tells her that the Consortium meeting is about to start. Later, Eleanor tells Ned Low he is to leave the island. O'Malley puts a sword to Ned's throat and they start to fight. Ned slashes O'Malley in the stomach and puts his sword to the back of O'Malley's neck. Eleanor tells Ned to stop, but he kills O'Malley.