The Doctor and Nasreen Chaudry go deep underground and find an ancient society that has been disturbed by the drilling. They are gassed and taken prisoner just as Amy manages to free ... See full summary »




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Episode complete credited cast:
Nia Roberts ...
Stephen Moore ...
Alun Raglan ...
Sam Davies ...
Elliot (as Samuel Davies)


The Doctor and Nasreen Chaudry go deep underground and find an ancient society that has been disturbed by the drilling. They are gassed and taken prisoner just as Amy manages to free herself. The military commander of the underground reptilians, Restac, is convinced that the "apes' - their term for humans - are an invading force. Calmer heads prevail and the Doctor manages to negotiate a truce pending the transfer of prisoners which he, and some of the more pacifist members of the reptilians, hopes will lead to a lasting peace. The only problem is that Alaya, the reptile prisoner has been killed and Restac is ready to go to war. Written by garykmcd

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Release Date:

29 May 2010 (UK)  »

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Aspect Ratio:

16:9 HD
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Did You Know?


This episode takes place in 2020. See more »


When Rory, Ambrose, and Tony arrive in the Silurians' court, after the Doctor asks what happened to Alaya, the camera cuts to Ambrose, standing with her head over Elliot's right shoulder. When the camera cuts back to her, she's now standing with her head over his left shoulder instead. See more »


[Elliot has just been awakened from artificial slumber]
Elliot: But where are we?
Mo: Well, I've got to be honest with you, son. We're in the centre of the Earth, and there are lizard men.
See more »


Featured in The Culture Show: Me, You and Doctor Who (2013) See more »


Doctor Who Theme
Written by Ron Grainer
Arranged by Murray Gold
Performed by BBC National Orchestra of Wales
See more »

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User Reviews

Unispired but not without It's surprises
30 May 2010 | by (Clydebank, Scotland) – See all my reviews

After last weeks entertaining and promising if flawed opening to this two part story, "Cold Blood" carries on from where "The Hungry Earth" an episode which owed much to the classic B-movie "Invaders from Mars", writer Chris Chibnall continues with the tale to deliver what ultimately culminates in a shockingly powerful and emotional denouement. To some extent a lightweight story with some hairy moments it eventually goes to some very dark places very quickly with a story that neatly exploits the fragility and basic flaws of human nature and the brutality and hatred that prejudice can instill in people.

Starting where the previous episode left, with the Doctor and Nasreen Chaudry, head of the mining expedition seen the previous week, having discovered that all tat consists of the Silurian race is not a mere tribe but a whole civilisation. In an attempt to prevent a potential war the Time Lord intends to exchange a Silurian who he along with the humans had captured in return for the humans in their possession who include Amy. The Silurian's as revealed before want control over the Earth again and plot to exterminate every single human off the face of the planet but the Doctor wishes to broker a deal which would allow both humans and Silurians to share the planet. But achieving such an aim might be more difficult than imagined. Especially when the worst that can happen, does.

"Cold Blood" marks the best script penned by Chibnall thus far when you consider some of his less rewarding work on "Torchwood" for example. It's tightly paced, with sympathetic and likable characters and although it occasionally wallows in sheer cheesiness and arguably relies on the odd plot contrivance to further it's basic yet effective plot, it's never the less a tort and thrilling run around. There are ultimately a number of the predictable clichés which come with a story regarding what is essentially the clash of two cultures who eventually have to fight to find some common ground. The fact that the Silurian prisoner Alaya is actually the sister of Resctac the military commander of the reptilian race seems all too convenient a plot device to provoke further animosity while Restac her self as with her sister are never properly developed and come across as just two angry two-dimensional caricatures who merely spit out venomous bile about humans. And there are of course the requisite, more benign Silurian protagonists although given the plot are more or less a necessity.

It's thank god then that the stories denouement partially makes up for these flaws with a chilling and emotional climax which would hopefully silence detractors who have accused the show as being too sugar coated and aimed at kids. Like "The Waters of Mars" it has an exceedingly grim conclusion although arguably more effectively handled and less heavy handed, utilising the tale to include the cracks in time seen throughout the series beautifully. The episode nicely exploits the callousness and perhaps the ultimate futility of war when understanding and diplomacy would be better used with Smith's Doctor playing mediator or peacemaker. Even the humans and not simply the Silurians are not totally depicted as being entirely good or bad and the shades of grey that consist in every one of us are employed with sublime craftsmanship as with nobility seen on either side.

The performances as has more or less been seen to be through out the fifth series are uniformly excellent with both Smith and Gillan once again proving to be as ever dependable in their respective roles with Gillan in-particular worthy of note giving it her all in the stories shocking climax. As is the same can be said for Arthur Darvill as Rory who proves to be growing to be more and more endearing. Inspired support as displayed in THE from Meera Syal, Robert Pugh, Nia Roberts et al while Samuel Davies as young Elliot may very well be an up and coming name to look out for in future. And It's largely due not only Davies likable performance but Chibnalls characterisation that Elliot doesn't slip in to the usual pitfall of an irritating, contrived child protagonist.

A solid then if not overwhelming classic episode which neatly concludes this two parter CB highlights the upward spiral of the Moffat era. Enjoyable, intelligent although perhaps hardly inspired or original it's never the less without it's surprises and with hints that the best and most shocking might be yet to come I can only hope Moffat delivers on his promise.

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