Thanks to the BBC's ill-advised junking of massive numbers of programs in the 1970s,the season seven classic "Inferno" was one of a number of Pertwee adventures that, for a time, the BBC only held in black and white. Fortunately colour copies of many of these were recovered from Canada in the early 1980s. However, these were adapted to the NTSC format to make them suitable for broadcast over there, and when converted back to our PAL format, suffered from a few unwelcome artifacts that tend to be an issue for these conversions - somewhat washed out colours, yellow skin tones and jagged movement. For the 2006 release, the BBC did their best to sort out these problems and improved the picture a lot. But time marches on, and technology now allows a better result than was possible in 2006. So the Restoration Team revisited the story. They used a procedure called "Vidfire" which is a computer program that smoothes out movement. Furthermore, they also used a method that had worked wonders with other stories such as "Inferno"s successor, "Terror of the Autons", synchronising the flawed colour with their high-definition monochrome recording, giving a sharper look to the colour.
Enough of the technical issues, what about the story ? This is simply a superb adventure, possibly the best of Pertwee's entire tenure. The basic premise - a drilling project unleashes doomsday upon the world - would have been difficult to sustain over seven episodes, so they came up with the imaginative idea of sending the Doctor into a parallel world (thanks to his continuing efforts to defy the Time Lords by getting the Tardis working again). In this other world we meet alternative versions of his colleagues who are not as likeable as those on "our" world.
Liz Shaw, instead of the warm, humourous, intelligent scientist we got to know during her brief tenure, is a cold, dispassionate person. The Brigadier, far from the fair UNIT commanding officer of the "real" world, is a bullying, fascistic coward. Benton is a violent thug. All of them are willing to assume that the Doctor is a spy and have him shot.
Professor Stahlman, the villain of the piece in both dimensions, is an incredibly rude and arrogant man. He is at odds with Keith Gold, the executive director, drilling consultant Greg Sutton, the Brig (whom he calls a pompous military idiot) and of course the Doctor. He simply will not listen to advice or warnings.
The production exudes an aura of impending disaster, and for once, thanks to the parallel world idea, we actually see the disaster happen rather than being averted. This could not have been done on Who too often, of course.
There are the usual features - a good commentary which was recorded some time ago and features the late Nicholas "Brigadier" Courtney and producer Barry Letts, an excellent (and longer than usual) "making of" documentary and part one of a Unit history (part two is on the Day of the Daleks DVD and we're still waiting for part three). All these were on the 2006 release, but here another feature has been added, in which Toby Hadoke reunites four members of the Havoc team who once again deliver superb stunt work here - boss Derek Ware, Stuart Fell, Roy Scammell and Derek Martin (now known to Eastenders fans as Charlie Slater) and is taught how to execute a stunt fall. An entertaining feature, but not one that on its own would justify purchase of the title for those who already have the 2006 release. What clinches it for me is the superb picture quality. Thoroughly recommended.