Jack is the younger brother of Pia. He was born in Ardougne in 5.156 and travelled eastwards into Misthalin with his sister, stealing along the way.
Later, around the Midsummer Festival of 165, he helped her impersonate Kara-Meir in the Flying Donkey Inn in Varrock and pretended to be her servant as part of a scheme for the Phoenix Gang. The next day the two made off with the money they had collected from people but were captured by the Phoenix Gang members within an hour. Jack quickly hid as he had been told to by his sister while Pia was stuffed in a barrel of apples and rolled down a hill, as is Straven's customary punishment for traitors.
Pia was then taken by Sulla's men, who figured he would need her, and followed them. He encountered the real Kara, along with Arisha and Gar'rth, however and, with bruises and bloody feet, took them to where his sister was being held hostage. There, Kara-Meir entered and barricaded the door, engulfing the house in total darkness as Pia had just knocked over the only lamp.
Kara-Meir proceeded to slay 12 of the 15 bandits within (one, Owen, was accidentally killed by Velko while another one was also killed by a friend) and took one, Velko, hostage when he pleaded for mercy. She freed Pia, who embraced her brother, but was angry when informed that Sulla, Jerrod and Barbec had left prior.