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