Guest Stars Emily Carey as Mary Conan Doyle Noah Jupe as Kingsley Conan Doyle James Lance as Barrett Underhill Blake Harrison as Lyman Biggs Sebastian Croft as Newsie Mary Healey as Mrs. Blake Tereza Srbova as Natalia Kroshenko Tommy McDonnell as Nigel Pennington Craig Conway as Angus Tuttle Paddy C. Courtney as Gaines Dean Forster as Herbert Ogilvie Natasha Sparkes as Sophie Helen Millar as Isobel Underhill Scott Jenkinson as Spring Heel'd Jack Dritan Kastrati as Vladimir Patlinov