Recurring Guest Characters Lars Tharp 13 guest appearances Janina Ramirez 11 guest appearances Professor Kate Williams 10 guest appearances Benedict Allen 3 guest appearances Marcus du Sautoy 2 guest appearances Helen Czerski 2 guest appearances Hallie Rubenhold 2 guest appearances Jacky Klein 2 guest appearances Simon Thurley 1 guest appearances Miranda Krestovnikoff 1 guest appearances Michael Scott 1 guest appearances Andrew Graham-Dixon 1 guest appearances Anna Keay 1 guest appearances Admiral Lord West 1 guest appearances Dan Cruickshank 1 guest appearances Dr. Gus Casely-Hayford 1 guest appearances Dr. Suzannah Lipscomb 1 guest appearances Dan Snow 1 guest appearances Professor Angie Hobbs 1 guest appearances Dr. Ayla Lepine 1 guest appearances ⇤ « 1 2 » ⇥