Michael Weston Harry Houdini Actor Stephen Mangan Sir Arthur Conan Doyle Actor Rebecca Liddiard Constable Adelaide Stratton Actor Adam Nagaitis George Gudgett Guest Star Tim McInnerny Horace Merring Guest Star Blake Harrison Lyman Biggs Guest Star Sebastian Croft Newsie Guest Star James Lance Barrett Underhill Guest Star Scott Jenkinson Spring Heel'd Jack Guest Star Helen Millar Isobel Underhill Guest Star Noah Jupe Kingsley Conan Doyle Guest Star Emily Carey Mary Conan Doyle Guest Star Paddy C. Courtney Mr. Gaines Guest Star Craig Conway Angus Tuttle Guest Star Tommy McDonnell Nigel Pennington Guest Star Tereza Srbova Natalia Guest Star Mary Healey Mrs. Blake Guest Star Natasha Sparkes Sophie Guest Star Dean Foster Herbert Oglivie Guest Star Dritan Kastrati Vladimir Palinov Guest Star Gary Davies Sgt. Chris Johnston Guest Star David Shore Executive Producer Kenton Allen Executive Producer Matthew Justice Executive Producer Luke Alkin Executive Producer Christina Jennings Executive Producer Maggie Murphy Executive Producer Scott Garvie Executive Producer