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 Amanda Abbington as Mary Morstan Sian Brooke as Eurus Holmes Simon Kunz as Sir Edwin Wanda Ventham as Mrs Holmes Timothy Carlton as Mr. Holmes Ralph Ineson as Vince Art Malik as Prison Governor Indica Watson as Little Eurus Rhys Rusbatch as Technician Brett Allen as Special Unit Guard Aaron Richards as Young Mycroft Honor Kneafsey as Girl on Plane Clare Foster as Velma Paul Weller as The Viking Tam Mutu as Leonard Richard Crehan as Ben Tom Stoughton as Young Sherlock Harry Tuffin as Victor Trevor Matt Young as Young Police Officer
