John Sessions

as Joseph Tomelty as Marley

as Bishop Tarcinkus (1 episode)

as Pumpermann

as Self

as Brownlow

as Presenter

as Mike Abbott

as Pere Tanguy

as DCI Frank Smilie (6 episodes)

as Prof. Richard Evans

as Lord John Russell (8 episodes)

as Doctor McLaren

as Lord Inquisitor (1 episode)

as Dr. Hermann

as The Accountant

as Ted Lowe

as Arthur Lowe

as Lord Boothby

as Narrator

as Mycroft Holmes

as Self - Narrator (voice)

as John Murray (1 episode)

as Mr. Smith

as Arthur Duncan (2 episodes)

as Thorne