Jack is a Greek immigrant who works alongside Henry at Glimmer & Company. He serves as something of a mentor for Henry, since he’s been a spy for a very long time and is thus very knowledgeable about the trade. In fact, he no longer works undercover like the rest of his colleagues, having informed Dennis Hoagland that he didn’t want to do so anymore. However, because Jack is such a valuable asset, Hoagland has forced him to stay on as a consultant of sorts, asking him to oversee the other operatives, all the while dangling the promise of full retirement as a way of keeping Jack invested in the job. The reason Hoagland sees Jack as so valuable is because of Jack’s past as an operative for the CIA in Greece, where he was often in dangerous situations, meaning that he’s quite experienced—and that he has seen and done some very violent things. Nonetheless, Henry likes Jack and frequently asks him for relationship advice, since Jack had a long, happy marriage until his wife died of cancer. Despite their close relationship, though, it becomes increasingly clear over the course of the novel that Jack will remain loyal to Hoagland by pressuring Henry to do various things he doesn’t want to do. Jack doesn’t like making things difficult for Henry in this way, but he’ll do seemingly anything to make sure he’ll be able to retire soon. He thus pressures Henry into stealing the list of people who contribute to John Kwang’s “money club,” which is the vital information that Glimmer & Company has apparently been hired to obtain.