For once, the TARDIS arrives at a bucolic English village roughly when it's meant to - only to find that apart from a rather dangerous greeting from some men in white hazmat suits, there seems to be nobody about. They find the pub, empty, and from there see a truck load of rather inanimate villagers arrive. That's the start of their adventure as they realise that things are not as they should be and that an external force is pulling the strings. Why? Well, we begin to get an inkling when they encounter the eye-patched space traveller "Crayford" (series regular Milton Johns) who has made some rather interesting friends who have completely duped him into believing in their peaceable intent. The "Doctor" (Tom Baker) with "Sarah Jane" (Elisabeth Sladen) and "Harry" (Ian Marter) have some good fun with this four-parter as there's a fair bit of replicating, a pursuing "UNIT" - who luckily couldn't hit a barn door with a shovel, and some energetic baddies who have something of the Jurassic about them. The writing is engagingly light-hearted and the make up team have done a fine job.