Guest Stars T.R. Knight as J. Edgar Hoover David Dencik as Niels Bohr Jodhi May as Helen Dukas Nikola Djuricko as Leo Szilard Jolyon Coy as Max Laue Robert Picardo as Abraham Flexner Rob LaBelle as Henry Morgenthau Ania Bukstein as Margarita Konenkova Adam Garcia as Moe Berg Karel Dobrý as Mikhail Ivanushkin John Sackville as R. Davis Halliwell Christian Rubeck as Werner Heisenberg Co Starring Zita Téby as Older Ilse Nancy Crane as Eleanor Roosevelt Lucy Farrett as Older Margot Miles Richardson as Vannever Bush Jim High as British Guard Bryan Bounds as Judge Steve Mirer as Doctor Timo Willman as Young Nazi Daniel Kötter as Gestapo Officer Charlie Field as Carl Von Weizsacker Gunnar Cauthery as Joseph Goebbels Stephen Chance as Paul Scherrer Georg Nikoloff as Sergei Konenkov Mitchell Mullen as Franklin Roosevelt Tom Knight as Waspy Donor David Hunt as General Leslie Groves