Transmitting down from Nerva Beacon, the Doctor, Sarah and Harry find themselves on Earth in the far future, long-side abandoned by the human race. But it soon becomes clear that they are not alone: a shipwrecked crew of Galsec colonists are being hunted down, one by one. What is the creature that lives in the rocks, and what is the purpose of the lethal tests it is conducting? Can the Doctor ensure the safety of the Earth for the future generations of Mankind?
   
-- from the DVD release, 2006

Originally released on VHS with its neighbour, Genesis of the Daleks, The Sontaran Experiment was chosen as the first of the budget range of Doctor Who releases, with a lower RRP and fewer bonuses.

Episode timings on DVD: 24'10", 25'04"
Episode timings on PasB: 24'27", 25'00"
 

Built for War (39'49")

A look at the various Sontaran appearances throughout Doctor Who.

• Terrance Dicks explains the concept of the Sontarans, how they came about and why Robert Holmes was chosen to write their introduction (and his reaction).
• Anthony Read and Elisabeth Sladen share their memories of Holmes.
• Sladen also discusses Kevin Lindsay and she and Dicks discuss the costume design and Dicks talks about the Target novelisation.
• Bob Baker then talks about The Sontaran Experiment, the restrictions put in place and Holmes' explanation of Sontaran history.
• Sladen recalls Lindsay's heart causing problems during filming and her relationship with Hinchcliffe, Stuart Fell recalls doubling, Baker recalls how they came up with the name Styre and Fell Tom Baker being replaced by Terry Walsh on set.
• Dicks takes a brief sidestep to talk about Horror of Fang Rock and how he decided, late into the script, that the enemy would be the Rutan.
• Read explains his feelings behind The Invasion of Time.
• Fell and Read discuss the casting, with the former explaining his glee at being a Sontaran in a swimming pool.
• Finally, discussion turns to The Two Doctors, with Eric Saward explaining why he brought the Sontarans back and his discussions with Nathan-Turner about the location shooting, Colin Baker their various positive qualities and Nicola Bryant the costumes.
• Baker and Saward then go on to talk about A Fix with Sontarans, and Dicks wonders if President Bush would get along well with the Sontarans

Clips are letterboxed to remain in 4:3
Built For War featured Bob Baker, Colin Baker, Nicola Bryant, Terrance Dicks, Stuart Fell, Anthony Read, Eric Saward, Elisabeth Sladen
Squadron Commander GRON: Mick Broster
Colourist: Jonathan Wood
Camera: Une Herzer
Sound: Angus Anderson
With thanks to Richard Bignell, Tony Clark, David Harley, Derek Handley, Doctor Who Magazine
Produced by Richard Molesworth
Produced and Directed by Steve Broster
(C) 2006 2Entertain
 
Photo Gallery (4'39")
47 b/w and colour photos from the production, and five production sketches.
Thanks to Richard Bignell, Ian Rutter, BBC Photo Library
(C) 2006 2entertain

Commentary
By Elisabeth Sladen, Philip Hinchcliffe and Bob Baker.

Info Text
By Martin Wiggins.