Sir Derek Jacobi is an English actor, best known to TV audiences for the title role in ''Series/IClaudius''. Other notable screen roles include the title role in ''Series/{{Cadfael}}'', Sen. Gracchus in ''Film/{{Gladiator}}'', Alan Turing in ''Theatre/BreakingTheCode'', Madson in ''Film/DeadAgain'', and the narrator of ''In the Night Garden''. He voiced the Master in the ''Series/DoctorWho'' animated special ''WebAnimation/ScreamOfTheShalka'' before guest-starring as the same character in the series proper in the episode [[Recap/DoctorWhoS29E11Utopia "Utopia"]]. He also appeared in an episode of ''Series/{{Frasier}}'' as a thespian who, when Niles and Frasier were children, introduced them to the wonder of the theatre. When they met him again as adults and helped him get his own one-man show, [[CastingGag he wasn't as good as they remembered.]] Many of the younger readers will know Derek Jacobi as Nicodemus from ''WesternAnimation/TheSecretOfNIMH''. More recently, he appeared as the Archbishop of Canterbury in ''Film/TheKingsSpeech'' and Cardinal Orsini in ''Series/TheBorgias'', promising some wonderful acting alongside Creator/JeremyIrons... until he was [[DeadStarWalking poisoned in the very first episode.]] He has starred with Creator/IanMcKellen in a series called ''Series/{{Vicious}}'', a gay DomCom about [[GrowOldWithMe a long-partnered male couple]].

He also has a distinguished stage career, having got his big break in Creator/LaurenceOlivier's National Theatre company, including [[ShakespearianActors lots of Shakespeare]]; he has played Theatre/{{Hamlet}} over 400 times on stage, not to mention his performance in the BBC's Complete Television Shakespeare. (He was also in Creator/KennethBranagh's film version of ''Hamlet'', as Hamlet's villainous uncle -- another Claudius -- in addition to his role as Chorus in Branagh's ''Theatre/HenryV''.)

He is married to fellow actor Richard Clifford, who is another to appear in many of Creator/KennethBranagh's Shakespeare films, though curiously the two never appeared together.

He was knighted for Services to Drama in 1994.