The third, fourth and fifth stories of the twentieth season were conceived by John Nathan-Turner and Eric Saward as a trilogy reintroducing the Black Guardian.
Mawdryn Undead
The Black Guardian recruits a young man named Turlough to assassinate the Doctor. Although outwardly an ordinary pupil at a boys' private boarding school, Turlough is in fact an alien who believes that the Guardian will return him home if he succeeds.
• Commentary -with actors Peter Davison, Mark Strickson and Nicholas Courtney, script editor Eric Saward.
• Who Wants to Live Forever? (dur. 24' 30") - cast and crew look back at the making of the story. With actors Peter Davison, Nicholas Courtney, Mark Strickson, David Collings and Lucy Benjamin, director Peter Moffatt, script editor Eric Saward and plastic surgeon Dr. Simon Withey. Narrated by Floella Benjamin.
• Liberty Hall (dur. 7' 19") - a new drama. Journalist Philip Clarke (Simon Ockenden) travels to Brendan School to interview Brigadier Lethbridge Stewart.
• Deleted and Extended Scenes (dur. 5' 14") - deleted and extended scenes from the location filming.
• Film Trims (dur. 3' 31") - film trims from the location filming, including clapperboards and cast and crew setting up and performing various takes.
• Out-takes (5' 33") - the producer's blooper reel.
• CGI Effects - this option allows the viewer to watch the story with a number of original effects shots replaced by new computer-generated images.
• Continuity (dur. 0' 55") - BBC1 continuity announcements from the story's original transmission.
• Set Photo Gallery (dur. 1' 35 ") - Set design photos from the story.
• Isolated Score - option to watch the story with the isolated music score.
Terminus
The TARDIS attaches itself to a space liner after Turlough, still under the Black Guardian's influence, damages its controls. The Doctor and Nyssa meet two space pirates, Kari and Olvir, who have come on board the liner in search of plunder, while Tegan and Turlough get lost in the infrastructure.
• Commentary with actors Peter Davison, Mark Strickson and Sarah Sutton, writer Stephen Gallagher.
• Breaking Point (dur. 22' 32") - cast and crew look back at the making of the story. With actors Peter Davison, Mark Strickson, Sarah Sutton and Martin Potter, director Fiona Cumming, writer Stephen Gallagher, designer Dick Coles, camera supervisor Alec Wheal and sound supervisor Scott Talbott. Narrated by Floella Benjamin.
• Origins of the Universe (dur. 6' 28") - Sir Patrick Moore and, Dr. John Mason take a look at the science behind the Big Bang and the origins of the universe.
• Original Storyboards (dur. 1' 17") - production storyboards for the spaceship sequences, plus how the shots were realised on screen.
• Unused Model Shots (dur. 3' 29") - a selection of unused takes from the model effects shoot, taken from a timecoded production tape.
• CGI Effects - this option allows the viewer to watch the story with a number of original effects shots replaced by new computer-generated images.
• Continuity (dur. 1' 51") - BBC1 continuity announcements from the story's original transmission.
• Isolated Score - option to watch the story with the isolated music score.
Enlightenment
The White Guardian warns of impending danger and directs the TARDIS to what appears to be an Edwardian sailing yacht, the SS Shadow, but is actually one of a number of spaceships taking part in a race through the solar system, the prize being Enlightenment.
• Commentary with actors Peter Davison and Mark Strickson, writer Barbara Clegg and director Fiona Cumming.
• Winner Takes All (dur. 23' 47") - cast and crew look back at the making of the story. With actors Peter Davison, Mark Strickson, Janet Fielding, Keith Barron, Christopher Brown and Leee John, director Fiona Cumming, writer Barbara Clegg, costume designer Dinah Collin and camera supervisor Alec Wheal. Narrated by Floella Benjamin.
• Casting Off! (dur. 10' 33") - an actor's view of working on Doctor Who. With Peter Davison, Janet Fielding, Mark Strickson, Keith Barron, Christopher Brown and Leee John, with director Fiona Cumming.
• Single Write Female (dur. 5' 12") - writer Barbara Clegg looks back on her career and the writing of 'Enlightenment'.
• The Story of the Guardians (dur. 11' 53") - the Guardians have appeared in Doctor Who as far back as Tom Baker's era… but who - or what - are they? With Robert Luckham (son of the late White Guardian, Cyril Luckham), Sarah Leppard (daughter of the late Black Guardian, Valentine Dyall), Doctor Who Magazine editor Tom Spilsbury and Doctor Who Adventures editor Moray Laing.
• Storyboards (dur. 5' 56") - a dual-angle feature, in which visual effects supervisor Mike Kelt uses the original storyboards to explain how he went about planning and shooting the model effects sequences for the show. The disc should default to the main angle, but the viewer should be allowed to flip angles on their remote to see the model sequences full-frame.
• Isolated Score - option to watch the story with the isolated music score.
