Guest Stars Rupert Graves as DI Lestrade Una Stubbs as Mrs. Hudson Louise Brealey as Molly Hooper Mark Gatiss as Mycroft Holmes Andrew Scott as Jim Moriarty Lara Pulver as Irene Adler Oona Chaplin as Jeanette Danny Webb as DI Carter Rosalind Halstead as Kate Munir Khairdin as Creepy Guy Andrew Havill as The Equerry Luke Newberry as Young Policeman Richard Cunningham as Timid Man Thomasin Rand as Beautiful Woman Simon Thorpe as Businessman Todd Boyce as Neilson Rosemary Smith as Married Woman Anthony Cozens as Geeky Young Man Nathan Harmer as Phil Darrell Las Quevas as Plummer Peter Pedrero as Archer Honor Kneafsey as Little Girl Ilana Kneafsey as Little Girl