Janet McTeer's MobLand Character Explained: Who Is Kat?

MobLand episode 7 saw Richie Stevenson strike a major blow against the Harrigans, but he was prevented from doing any further damage by Janet McTeer’s mysterious new character. The ending of episode 7 saw Harry call in a favor to parties unknown to prevent the death of Seraphina Harrigan at the hands of Jaime Lopez, a cartel boss acting on behalf of his business partner, Richie Stevenson. The call came too late to save Conrad and Maeve’s oldest son, Brendan Harrigan, who met a gruesome end as retaliation for the murders of Tommy and Vron Stevenson.