As the weed breaks into the Pipeline Room at the refinery, the deranged Chief Robson kidnaps Victoria in a helicopter and heads for the Control Rig.

The Ice Warriors have taken control of Peladon. Pretending to cooperate, the Doctor concocts a plan to defeat the invaders

Alisha Bailey played Isabella in the 2010 Doctor Who television story The Vampires of Venice

Also appeared in The Decoy Bride, Dirk Gently, Missing, My Almost Famous Family, Doctors

Simon Paisley Day is a British stage and screen actor. 

He played the Steward in the 2005 story The End Of The World

His most recent work includes Timon Of Athens (2008), Entertaining Mr Sloane (2009), Private Lives (2010) and Twelfth Night (National Theatre, 2011).

Graham Duff is an English writer, actor and producer. 

His work for TV and radio is typified by intricate plotting, large casts, frequently dark subject matter and a love of wordplay and surrealism. 

His writing is influenced by the worlds of horror and science fiction, musical sub-cultures and the realms of fine art and art house cinema. He is a noted music enthusiast, having worked as a DJ and selected all the soundtrack music for seven series of his TV show Ideal, as well as curating an Ideal soundtrack album and helping to release albums by the left-field bands Celebricide and Cyclobe. 

He also worked as a script editor on seven series of BBC Radio 4's 'Count Arthur Strong's Radio Show!' and the Alan Partridge movie 'Alpha Papa' (2013).

Peter Davison (born Peter Malcolm Gordon Moffett) was born Peter Moffett in Streatham, London, son of an electrical engineer who was originally from Guyana. Before becoming an actor, he attended Winston Churchill School, St John's, Woking, Surrey. He studied at the Central School of Speech and Drama. His first job was as an actor and assistant stage manager at the Nottingham Playhouse.

His first television work was in a 1975 episode of the children's science fiction television programme The Tomorrow People, alongside American actress Sandra Dickinson, whom he married on 26 December 1978. The couple composed and performed the theme tune to Button Moon, a children's programme broadcast in the 1980s. In 1977, Davison appeared in the TV miniseries Love for Lydia opposite Jeremy Irons.

In 1978, Davison's performance as as Tristan Farnon in the BBC adaptation of James Herriot�s All Creatures Great and Small made him a household name. Davison appeared in some British sitcoms, including Holding the Fort, Sink or Swim and Ain't Misbehavin', as well as appearing in dramatic roles.

In 1981, Davison was cast as the Fifth Doctor by producer John Nathan Turner. At age 29, he was at the time the youngest actor to have played the lead role. He stayed with the series for three years seeing it through a period when it lost its traditional Saturday evening slot and was shown twice weekly in the early evening. He returned to the role in the 1993 multi-doctor charity special Dimensions in Time and in the 1997 video game Destiny of the Doctors and once more in "Time Crash", a special episode written by Steven Moffat for Children in Need. He continues to reprise the role in a series of audio plays by Big Finish Productions.

Following his time in the series Davison played Dr Stephen Daker, the hero of A Very Peculiar Practice, written by Andrew Davies, and played the lead in Campion, a series based on the period whodunnits of Margery Allingham.

Davison has appeared in several radio series including Change at Oglethorpe in 1995 and Minor Adjustment in 1996. In 1985 he appeared in the BBC Radio 4 comedy drama series King Street Junior, as teacher Eric Brown. In 1994, he provided the voice of Mole in the animated special of The Wind in the Willows Mole's Christmas.

Davison has had a considerable stage career. In 1984, he appeared in Neil Simon's Barefoot in the Park at the Apollo Theatre and in 1991, in Arsenic and Old Lace at the Chichester Festival Theatre. Other theatre appearances include: The Last Yankee, by Arthur Miller at the Young Vic Theatre and later the Duke of York's Theatre, London in 1993, and Vatelin in An Absolute Turkey, by Georges Feydeau, at the Gielgud Theatre in 1994. In 1996 he played the role of Tony Wendice in the theatrical production of Dial M for Murder. He appeared as Amos Hart in Chicago at the Adelphi Theatre in 1999, and as Dr Jean-Pierre Moulineaux, in Under the Doctor at the Churchill Theatre, Bromley and later at the Comedy Theatre, London in 2001. Davison performed as King Arthur in the London production of Spamalot and as Professor Callahan in the West End production of Legally Blonde, which opened at the Savoy Theatre.

In November 2010 it was announced that Davison would be joining the regular cast of the UK version of Law and Order as Henry Sharpe, the Director of the CPS.

Tony Dow  is an American film producer, director and sculptor, and a television child actor of the 1950s and 1960s.

Dow is best known for his role in the television sitcom Leave It to Beaver, which ran in primetimefrom 1957 to 1963. Dow played Wallace "Wally" Cleaver, the elder son of June (Barbara Billingsley) and Ward Cleaver (Hugh Beaumont), and the brother of Theodore "Beaver" Cleaver(Jerry Mathers).

Dow was the visual effects supervisor for the 1996 TV Movie

Julian Fox played Peter Hamilton in the 1974 Doctor Who story Death to the Daleks.

Also worked on The Wingless Bird, Ruth Rendell Mysteries, Anglo Saxon Attitudes, Van der Valk, The Chief, A Very British Coup, Gems, The Charmer, Drummonds, Black Silk, The Last Place on Earth, The Nation's Health, Play for Today, Prisoners of Conscience, Blood Money, Escape, Secret Army, BBC2 Playhouse, Target, Stand Up, Virgin Soldiers, Yes, Honestly, The Naked Civil Servant, Microbes and Men, Fall of Eagles, Bowler, The Rivals of Sherlock Holmes, ITV Sunday Night Theatre, Colditz, The Last of the Baskets, The Troubleshooters, Mr. Rose, It Happened Like This

David Fisher wrote several television scripts and novelised two of his stories as Doctor Who and the Creature from the Pit and Doctor Who and the Leisure Hive. 

Fisher wrote another script for Doctor Who called The Gamble With Time. He was unable to revise it, so it was altered by others. It became City of Death and was produced under the pseudonym David Agnew.

Also worked on Hammer House of Mystery and Suspense, Hammer House of Horror, The Mackinnons, General Hospital, Crown Court, Sutherland's Law, The Lotus Eaters, Crime of Passion, The Troubleshooters, Dixon of Dock Green, This Man Craig, Orlando

Eric Pringle was a British writer for radio and television who lived in the Lake District.

His work included the television series Pretenders (1972), Kate (1972) and The Carnforth Practice (1974), and the radio play Hymus Paradisi (2001) about the life of composer Herbert Howells, for which he won a Sony Award for Best Music Feature. He also wrote adaptations for a number of authors' works, including Thomas Hardy, HE Bates, Joan Aiken's The Wolves of Willoughby Chase, and JB Priestley's The Good Companions.

His association with Doctor Who came through his agent, former producer Peter Bryant, submitting two stories for consideration in August 1981, The Darkness and War Game. The latter eventually became commissioned as the two part story The Awakening for transmission in 1984. He adapted the story as a Target novelisation in 1985.

His 1993 play about Beatrix Potter, Meeting Bea, was adapted to celebrate the 150th Anniversary of the author's birth at the Old Laundry Theatre in Bowness Cumbria in 2016 at the suggestion of its patron, Victoria Wood.

2001 saw the author's first book for children published, Big George, a science fiction retelling of the legend of St George and the Dragon. This was followed up by two sequels, Big George and the Seventh Knight, and Big George and the Winter King.

He died in 2017 after suffering from lung cancer, and is survived by his wife Jenny, children David and Susannah, and granddaughter Bethany.

Gareth Thomas was a Welsh actor best known for the part of Roj Blake in Blake's 7

Thomas trained at RADA and was an Associate Member. He was twice nominated for a BAFTA for his performances in Stocker's Copper (BBC Play for Today) (1972) and Morgan's Boy (1984).

Some of his other television appearances included The Avengers, Coronation Street, Z-Cars, Special Branch, Sutherland's Law, Public Eye, Star Maidens, Who Pays the Ferryman?, Bergerac,By the Sword Divided, The Citadel, Knights of God, Boon, London's Burning, Casualty, Taggart, Heartbeat, Sherlock Holmes, How Green Was My Valley, Torchwood and Midsomer Murders.

Thomas also appeared on stage in many productions. Notable appearances include RSC productions of Twelfth Night, Othello and Anna Christie; English Shakespeare Companyproductions of Henry IV, Part 1 and Part 2 and Henry V; and King Lear, Educating Rita, Cat on a Hot Tin Roof, The Crucible, Equus and DVu. In 2010 Thomas gave an acclaimed performance as Ephraim Cabot in Desire Under the Elms at the New Vic Theatre.

In 2001 he appeared in Storm Warning, an audio drama based on Doctor Who by Big Finish Productions. He also played the part of Kalendorf in the Big Finish Productions Dalek Empireseries. In 2006 he appeared as a guest star in the Doctor Who spin-off series Torchwood, in the episode "Ghost Machine". In 2012, Thomas returned to the role of "Roj Blake" in Big Finish Productions' Blake's 7: The Liberator Chronicles, a series of dramatic readings which take place during Series One before the death of Oleg Gan. Thomas stars as "Blake" in Counterfeit by Peter Anghelides and False Positive by Eddie Robson.

He married three times, having two children from his first marriage, Anna and Glyn; his second wife was make-up artist Sheelagh Wells, and was married to his third wife Linda for some 25 years.

Richard Gibbon Hurndall was an English actor who played the First Doctor in the 20th Anniversary story.

Hurndall was born in Darlington and he attended Claremont Preparatory School, Darlington and Scarborough College, before training as an actor at the Royal Academy of Dramatic Arts. He then appeared in several plays at Stratford-upon-Avon. Hurndall acted with the BBC radio drama repertory company from 1949 to 1952.

In 1958 he became the third host of the Radio Luxembourg program called This I Believe. (This show had originally been hosted by Edward R. Murrow on the U.S. CBS Radio Network from 1951 to 1955 and it was then edited in London for rebroadcast on 208 with a British style of presentation at 9:30 PM on Sunday evenings.)

Hurndall appeared in numerous radio and stage plays, films and television series over the course of his lengthy career, including The Avengers, The Persuaders!, Blake's 7, Whodunnit! and Bergerac. He played the suave London gangster Mackelson in the 1968 drama series Spindoe, had a recurring role as a senior civil servant in the final series of The Power Game and did a camp turn as a gay antique dealer who takes a shine to Harold Steptoe in the comedySteptoe and Son. He appeared twice in the series Public Eye, playing a distinguished entomologist who is unwilling to trace his missing son in "The Golden Boy" (10 January 1973) and a priest in "How About a Cup of Tea?" (13 January 1975).

In 1983 Doctor Who, producer John Nathan-Turner planned a special event, The Five Doctors, a 90-minute episode to feature the four of the five actors who had at that point played the role of the Doctor.

William Hartnell, the actor who originated the role, had died in 1975. The show's unofficial fan consultant, Ian Levine, had seen Hurndall in Blake's 7, another BBC science fiction series, and suggested him to the producers as a possible replacement. Hurndall eventually won the role of the First Doctor, playing him as acerbic and temperamental but in some ways wiser than his successors. When Tom Baker, who played the Fourth Doctor, decided not to appear in the programme, Hurndall's role was beefed up slightly to have the First Doctor take a greater part in the action. Plans were then made for Hurndall to reprise the role in the 1985 story The Two Doctors but the actor's unexpected death led toPatrick Troughton replacing him in the story.

Richard Hurndall died of a heart attack at the age of 73 in London, less than five months after the first broadcast of The Five Doctors. Many sources, including Elisabeth Sladen's autobiography, have suggested that he died before being paid for the role.