Doctor Who and the Silurians
UNIT and the Doctor are summoned to a nuclear power research center located near a complex of caves; something has been slowly driving members of the center’s staff mad, one by one, and at least one spelunker has been killed in the caves. The Doctor investigates the caves for himself, uninterested in what initially seem like personnel problems at the center, and finds a living dinosaur inside them; he also discovers evidence of a bipedal reptile species, both in the caves and outside. The center’s director doesn’t believe the story he’s being told, but the Brigadier prepares UNIT to defend against a possible invasion. The Doctor is convinced that the reptile humanoids are Silurians, the original inhabitants of the Earth before a mass extinction wiped out most of the large reptile species and allowed humans to evolve and thrive. The few survivors of the event went into underground shelters, and the energy released by the research center is slowly awakening them. The Doctor is determined to contact them and try to talk them into coexisting peacefully with humans on the surface, only to find that warlike factions exist among the Silurians as well – and some of them will be satisfied with nothing less than wiping out humanity.
written by Malcolm Hulke
directed by Timothy Combe
music by Carey BlytonGuest Cast: John Newman (Spencer), Bill Matthews (Davis), Peter Miles (Dr. Lawrence), Norman Jones (Baker), Thomasine Heiner (Miss Dawson), Fulton Mackay (Dr. Quinn), Roy Branigan (Roberts), Ian Cunningham (Dr. Meredith), Paul Darrow (Hawkins), Pat Gorman (Silurian Scientist), Dave Carter (Old Silurian), Nigel Johns (Young Silurian), Paul Barton, Simon Cain, John Churchill (Silurians), Peter Halliday (Silurian voice), Nancie Jackson (Doris Squire), Gordon Richardson (Squire), Richard Steele (Hart), Ian Talbot (Travis), Geoffrey Palmer (Masters), Harry Swift (Robins), Brendan Barry (Doctor), Derek Pollitt (Wright), Alan Mason (Corporal Nutting)
Broadcast from January 31 through March 14, 1970
LogBook entry & review by Earl Green
The Doctor and Evelyn arrive at the Galapagos Islands, finding a young naturalist named Charles Darwin conducting research and observations there. The Doctor is a bit worried about Evelyn interfering with the development of Darwin’s theories, but he soon has more to worry about – prisoners at the local jailhouse disappear without a trace, and a woman is upset that her brother, whose mind has snapped after what he says was an encounter with “devils,” is scheduled for execution. Though the Doctor is less than impressed with the local governor’s demeanor, he soon realizes that something far more sinister is at work here – a small enclave of hibernating Silurians has awoken in their chambers deep below the islands, and one of them is plotting the destruction of homo sapiens… which may only be fair, since he created homo sapiens.
Called out of retirement to participate in a press conference following an apparent attack in the heart of London, Sir Alistair Gordon Lethbridge-Stewart finds that life as a member of the United Nations Intelligence Taskforce hasn’t changed a bit; a helicopter attacks the limo carrying him to deliver his speech. The driver is killed in the attack, but Lethbridge-Stewart’s steady aim helps to bring the helicopter down – where he discovers that its crew consisted of one human and one Silurian. Convinced that this incident has something to do with the planned handover of UNIT’s responsibilities within British borders to a new agency called ICIS, Lethbridge-Stewart takes drastic measures to preserve UNIT’s authority – even if it means blowing decades of covert operations involving alien invaders wide open.
Notes: This marks the first time Daleks, Cybermen and Sontarans have all shared the screen in anything other than a flashback (if one wishes to count flashbacks, however, the first time would have been during the flashbacks experienced by the fourth Doctor at the end of part 4 of 
Cast: Matt Smith (
Strangerers. This is the first on-screen evidence that the Silurians were capable of space travel; the Doctor’s previous encounters with them all involved enclaves of Silurians who opted to wait out the Earth’s extinction event in underground chambers. It could be that the Silurian space ark was a more desperate, radical attempt to preserve the Earth’s species. Ironically, this also gives the Silurians – normally enemies of the human race – something in common with their foes: both species, faced with imminent extinction-level events on Earth, took to space to preserve the planet’s life forms (also see Nerva Beacon in The Ark In Space). There seems to be no indication that other Silurian ships were launched. The notion of an artificially constructed beach providing the ship with hydroelectric power matches up well with previous evidence of Earthbound Silurians utilizing geothermal power. The Doctor’s warning about messing with Egyptian queens comes from experience; this may be a reference to the Big Finish audio stories, in which the fifth Doctor traveled with Erimem, the first female Pharaoh, following an attempt on her life.
Notes: The second Doctor encountered the 
Guest star Richard E. Grant was the ninth Doctor in an animated alternate universe in 2003’s 
Olivia Vinall (Effie), Michelle Tate (Abigail), Jack Oliver Hudson (Urchin Boy)
Huntsman.
(and stand-ins), William Hartnell has a speaking part in an episode of Doctor Who for the first time since the prologue of 1983’s 
The Great Intelligence mentions some of the Doctor’s “other names”, including “the Oncoming Storm” (the Daleks’ name for the Doctor, first revealed in the novelization of 1988’s 
Notes: The Doctor, in his tenth incarnation, encountered similar self-repairing robots aboard the S.S. Madame du Pompadour in The Girl In The Fireplace (2006), also written by Steven Moffat. This is the first post-regeneration story in the history of Doctor Who that features a new scene shot with the previous Doctor.