Owen Slater is a former member of the Irish Republican Army who met Nucky while he was working as a bodyguard an enforcer for Irish politician John McGarrigle. Slater, looking for a way to America, took a job as Nucky's bodyguard and an enforcer in Nucky's organization. Slater continues to handle some unfinished IRA business on the side in the States.Slater quickly becomes loyal to Nucky, who seems to keep a fairly skeptical eye on Slater -- and perhaps for good reason. Slater develops a friendly relationship with Margaret, who sees Slater as a reminder of her homeland. Margaret becomes jealous of a sexual relationship Slater sparks with one of the maids in their house and makes her disapproval known.Slater's skills as a hitman come in quite handy in Nucky's dealings and he is called upon to protect Nucky on several occasions. But Slater's brash and cocky approach to his job could cost him.