"A variety of prehistoric reptiles began to appear in the general London area. There was, as you can imagine, considerable panic and some loss of life."
Best known to many as the one with the shonky dinosaurs, Invasion of the Dinosaurs is one of the most anarchically anti-establishment Doctor Who stories of them all, the dinosaurs that mysteriously appear and disappear in the streets of an evacuated London merely a smokescreen for an elaborate conspiracy involving time travel, genocide and a rather overzealous approach to ecological issues. The conspiracy may have the usual suspects - politicians, scientists and the army - but they appear to be a curious mixture of extreme left-wingers and right-wingers who want to save the planet from the human race by wiping them out and starting all over in a golden age.
At the time of the show's production in 1973, green matters were still an issue led more from the extreme right than the left, but despite being written by a former communist the show also takes plenty of swipes at the dogmatic nature of the far left, with their `reminder room' and determination to kill anyone they can't successfully re-educate. Indeed, even its deceived `idealists' whose `guidance' will prevent the New Earth from making the same mistakes as the old are a narrow minded lot who are ultimately more angry at being tricked than at the prospect of human history and the entire human race - with a few politically correct exceptions - being `painlessly' erased. Even more intriguingly, one regular and very sympathetic character in the series at the time is in on the plot and is so devoted to the cause that he'll happily be erased himself if it helps usher in the new golden age. It's all the more surprising considering how many of the Jon Pertwee stories were driven by ecological issues to see the show offer villains with a similar agenda and technology, albeit much more ruthless methods, to the Doctor himself. Few long-running shows have ever challenged their hero's assumptions in quite the same way even if the point is played down.
None of which makes the dinosaur puppets any more convincing even if they are the work of veteran 007 special effects man Cliff Culley, though thankfully they're used fairly sparingly, as is the Whomobile, Pertwee's short-lived space-age replacement for the much-loved vintage car Bessie that was introduced in this story. But the strengths outweigh the problems, from the decent performances (including a very amiable Noel Johnson, once a huge star himself as Dick Barton on radio) to its willingness to slyly subvert the show's own formula. There's a good extras package too: the obligatory group audio commentary, five deleted scenes, an extended 2003 interview with Elisabeth Sladen about her time o the show, a location comparison, a brief extract from Billy Smart's Circus featuring Pertwee and the Whomobile and a very good half hour documentary on the making of the show and its subversive undertones. There's also the option to see the opening episode in black and white or in a highly inconsistently colorized version (the other five episodes are all colour, but the first only survives in a poor black and white copy).
The Terry Nation-scripted The Android Invasion is a more conventional affair and, despite being packaged as part of a UNIT collection, has only the most superficial UNIT presence (the last brief appearances of Ian Levine's Sergeant Benton and Ian Marter's Harry Sullivan) as Tom Baker's Doctor and Sarah Jane Smith arrive in a mysteriously deserted English village near a space defence centre. Not that it's deserted for long, but there's definitely something wrong about the inhabitants and the place itself, with the few familiar faces they encounter ready to kill them without a second thought, though it's not the androids who are regimenting their behaviour who turn out to be the ones with invasion plans. It's a decent enough story even if it is one of the ones that doesn't do much more than fill a four week part of the schedule between more memorable stories (in this case sandwiched between the excellent Pyramids of Mars and the enjoyable gothic Brain of Morbius) in the show's strong thirteenth season.
UNIT is completely absent from the extras, too: the usual audio commentary, a half hour making of that focuses on Terry Nation's return to the series with a nod to the similarities between this story and his work on The Avengers (the show even features `Mother' himself, Patrick Newell), a half hour overview of producer Philip Hinchcliffe's prestigious non-Doctor Who television work, an Easter Egg of some location sound rushes and a tie-in Weetabix commercial.