Doctors
David Tennant (Tenth Doctor)
Matt Smith (Eleventh Doctor)
Companion: Bernard Cribbins (Wilfred Mott)
Others
John Simm – The Master
Timothy Dalton – The Narrator / Lord President
Catherine Tate – Donna Noble
Jacqueline King – Sylvia Noble
Billie Piper – Rose Tyler
Camille Coduri – Jackie Tyler
Freema Agyeman – Martha Smith-Jones
Noel Clarke – Mickey Smith
John Barrowman – Captain Jack Harkness
Elisabeth Sladen – Sarah Jane Smith
Jessica Hynes – Verity Newman
Russell Tovey – Midshipman Alonso Frame
Thomas Knight – Luke Smith
June Whitfield – Minnie Hooper
Claire Bloom – The Woman
David Harewood – Joshua Naismith
Tracy Ifeachor – Abigail Naismith
Lawry Lewin – Rossiter
Sinead Keenan – Addams
Alexandra Moen – Lucy Saxon
Karl Collins – Shaun Temple
Teresa Banham – Governor
Barry Howard – Oliver Barnes
Allister Bain – Winston Katusi
Sylvia Seymour – Miss Trefusis
Simon Thomas – Mr Danes
Pete Lee-Wilson – Tommo
Dwayne Scantlebury – Ginger
Joe Dixon – The Chancellor
Julie Legrand – The Partisan
Brid Brennan – The Visionary
Krystal Archer – Nerys
Lacey Bond – Serving Woman
Lachele Carl – Trinity Wells
Paul Kasey – Ood Sigma
Ruari Mears – Elder Ood
Max Benjamin – Teenager
Silas Carson – Ood Sigma (voice)
Brian Cox – Elder Ood (voice)
Nicholas Briggs – Judoon (voice)
Dan Starkey – Sontaran
Production
Directed by Euros Lyn
Written by Russell T Davies
Script editor Gary Russell
Produced by Tracie Simpson
Executive producer(s) Russell T Davies
Julie Gardner
Incidental music composer Murray Gold
Production code 4.17 and 4.18
Series 2008–2010 specials
Length 2 episodes, 60 and 75 minutes
Date started 25 December 2009
On Earth, a cult resurrect Master (Simm), but his ex-wife, Lucy Saxon (Moen), sabotages the ceremony, causing the Master to be brought back with incredible strength but constant hunger.
Elsewhere, the Ood warn the Doctor (Tennant) that the Master has returned, heralding "the end of time". Arriving back on Earth on Christmas Eve, the Doctor encounters Wilfred Mott (Cribbins), grandfather of his former companion Donna (Tate), who helps track down the Master. The Doctor explains that he fears a prophecy about "he will knock four times" that will predicate his death. The Doctor finds the Master at wastelands outside London. The Doctor learns that the Master has been suffering from hearing the sound of drums, which is not associated with his insanity but implanted externally. Before the Doctor can learn more, the Master is taken by armed troops and placed in custody of billionaire Joshua Naismith (David Harewood). Naismith has recovered a broken alien "Immortality Gate" and wants the Master to fix its programming.
The Doctor regroups with Wilfred, who is able to identify Naismith. Wilfred prepares to go with the Doctor, but an apparitional woman in white (Bloom) warns him to arm himself to protect the Doctor before departing. At Naismith's mansion, the Doctor and Wilfred meet two Vinvocci disguised as humans, who assert the Gate is a harmless medical device from their homeworld. The Doctor is too late stopping the Master from activating the Gate, which he has reprogrammed to replace all of humankind's DNA with his own, making humanity his own "Master race"; only Wilfred, protected in the Gate's control rooms, and Donna, due to Time Lord biological traits she gained earlier, are unchanged. The Master and his doppelgangers taunt the Doctor, who can only look on in horror.
Elsewhere, the Lord President of the Time Lords (Dalton) observes the situation and asserts their plan can continue, and that the Time Lords have returned.
The End of Time Pt I