Injured by the Orgrons, the Doctor asks the Time Lords to send the TARDIS after the Daleks. Leaving him to sleep and recuperate, Jo goes to explore the planet Spirodon.

Clarke Peters is an American actor, singer, writer and director best known for his roles as Detective Lester Freamon and Albert "Big Chief" Lambreaux, on the HBO dramasThe Wire and Treme respectively

Janie Booth  voiced System in Torchwood The Harvest, an old woman in Medicinal Purposes, and Eve Morris in The Gathering. She also played a Hospital Patient in Dead Man Walking.

Has also appeared in Hell's Pavement, Doctors, Cockroach, Veils, As Time Goes By, Holby City, The Bill, Resnick: Rough Treatment, Lovejoy, The Blackheath Poisonings, Press Gang, Pulaski, Personal Services, All in Good Faith, Black Silk, Summer Season, Hallelujah!, Nanny, Terry and June, 1990, Doctor on the Go, Softly Softly: Task Force, Within These Walls, A Little Bit of Wisdom, His and Hers, Tales from the Lazy Acre, Upstairs, Downstairs, Comedy Playhouse, Not Only... But Also, The Wednesday Play, The Old Campaigner, Ukridge, Theatre 625, Othello

Arthur Cox  is a British actor of television and film.

His most regular role was as George, the driver of Jim Hacker in the comedy Yes Minister. His other television credits include The Avengers,Terry and June, and Harbour Lights. 

His roles of Cully and Mr Henderson in the Doctor Who stories The Dominators and The Eleventh Hour make him the record holder for longest gap between appearances on the series.

_{Biography from the Wikipedia article, licensed under CC-BY-SA}

Andrew Sachs was born in Berlin in 1930, but his family moved to England in 1938 to escape Germany (his father being Jewish) - they setlled in Kilburn, where the actor spent the rest of his life.

His acting career encompass stage, television and screen, with appearances in series like The Saint, Randall & Hopkirk Deceased, and the film The Night We Dropped A Clanger. However, it was as Spanish waiter Manual alongside John Cleese in Fawlty Towers that was to become his most famous role and a household name. He later appeared in some 27 episodes of Coronation Street as Ramsey, and also in the 2008 Christmas special of Casualty.

On radio, he portrayed Father Brown in the 1980s, and Doctor Watson in original Sherlock Holmes stories for BBC Radio 4 during the 2000s. He also played Professor Chronitis in a 2007 adaptation of Douglas Adams's Dirk Gently's Holistic Detective Agency, and Tooley in Neil Gaiman's Neverwhere in 2013.

He also played the voice of the Book in the live tour of Douglas Adams's The Hitch-Hiker's Guide to the Galaxy in 2012.

Though he never appeared in the television series, his Doctor Who credentials included playing Skagra in the Big Finish/BBC Online adaptation of another Douglas Adams creation, Shada, and also Big Finish audio adventures TheBoyThatTimeForgot and Orbis. He also appeared as Temmosus in the BBC Radio 4 audio play Whatever Happened To... Susan Foreman?.

As well as acting he was also a veteran narrator of numerous television and radio documentaries, including all five series of Troubleshooter; he also narrated several audio books, such as the Narnia series by CS Lewis.

In 2012 he was diagnosed with vascular dementia, but this was kept secret until his death in 2016.

His autobiography, I Know Nothing!, was published in 2014.

He married his wife Melody in 1960 (who also appeared in an episode of Fawlty Towers), and had a stepson John and grand-daughter Georgina.

Lawrence Davidson  had an uncredited role as the Draconian First Secretary in the 1973  Doctor Who story Frontier in Space.

Also worked on The Young Indiana Jones Chronicles, Bergerac, Harry Enfield's Television, Strike It Rich, Lytton's Diary, Agatha Christie's Partners in Crime, Curse of the Pink Panther, The Brack Report, The Dogs of War, Escape, Spearhead, Crown Court, BBC Play of the Month, Victorian Scandals, Man About the House, Oil Strike North, Churchill's People, Masquerade, New Scotland Yard, Colditz, The Dragon's Opponent, The Song of Songs, Man Who Was Hunting Himself, The Saint, Who Was Maddox?, The Edgar Wallace Mystery Theatre, Sergeant Cork, No Hiding Place, Sir Francis Drake, Danger Man, Pride and Prejudice

Tim Pigott-Smith was an English film and television actor.

Pigott-Smith was born in Rugby, Warwickshire, the son of Margaret Muriel (née Goodman) and Harry Thomas Pigott-Smith, who was a journalist. He was educated at Wyggeston Boys' School, Leicester, King Edward VI School Stratford-upon-Avon, and Bristol University. He trained as an actor at the Bristol Old Vic Theatre School.

Notable appearances included Ronald Merrick in The Jewel in the Crown, the title role in the crime drama series The Chief (1990-1993), a recurring role in ITV drama The Vice as Ken Stott's nemesis, Vickers, Bloody Sunday and two separate adaptations of North and South. In the 1975 version he played Frederick Hale, while in 2004 he played his father Richard.

His film career included the 2004 film Alexander, The Four Feathers, Gangs of New York, Johnny English, The Remains of the Day, and V for Vendetta. Tim also makes an appearance in the 2008 film Quantum of Solace.

Pigott-Smith was a regular stage actor in Shakespearean and Greek roles; for instance, he played Posthumus in John Barton's 1974 production of Cymbeline for the Royal Shakespeare Company. His most recent appearance was as Kenneth Lay in ENRON (2009).

He received an OBE in 2017.