Know Your Cybermen No.2

The Moonbase (1967).
The Cybermen return with a total design revamp. It is now the year 2070, and a group of Cybermen launch an attack on a Moonbase which contains the Gravitron - a machine which controls the weather on Earth.
These Cybermen are sleeker and more robotic. The heads are full helmets, with the forehead lamp now built in. They have the same black disc-like eyes, but the mouth is now a rectangular hole like a letter box. When speaking, a little door opens and closes in the mouth. The voice is artificially generated and machine-like.
They are not totally unemotional - having what appears to be a sense of irony, and are contemptuous of the humans.
They retain handle like projections at the sides of the skull. The chest unit is smaller and more compact, but still seems to fulfil the same heart and lung functions. They have three fingers on each hand (or rather a thumb and two fingers).
Their boots have what appear to be laces. Hydraulic tubing runs along the limbs and links to the chest unit. At the joints are spherical junction units.
Rather than launch a frontal attack on the Moonbase, the Cybermen elect to first infiltrate secretly and introduce a toxin - Neurotrope X - which they use to lace the base sugar supply. This renders its victims comatose, with the veins appearing black under the skin. The infected humans are abducted and taken to the Cyberman ship, where they are mentally conditioned to work for the aliens. They will be used to operate the Gravitron to cause havoc on Earth.
The reason for this seems more to prevent the humans becoming a threat to them, than any old-fashioned invasion attempt. The Cybermen cannot operate the Gravitron themselves as they are susceptible to strong gravitational fields.
Weaponry consists of hand held guns - with long rod-like barrels. They also have larger laser cannons. They can also generate an electrical charge from their hands which can stun.
The Doctor's companion Polly devises a weapon against them - a cocktail of solvents which dissolves their chest units. The main Cyber force is sent hurtling off into space by the Gravitron.

So, how can there be Cybermen in 2070, when Mondas and all its inhabitants were destroyed back in 1986? The redesign helps provide an answer. These are obviously some kind of warrior / explorer class, designed for space missions. At some point before Mondas returned to Earth, some Cybermen left their planet and set up bases / colonies on at least one other planet. It is from one of these that this group comes.

Story Notes:

• The redesign was prompted primarily by practicalities. With Terry Nation making noises about withdrawing permission to use the Daleks, the Cybermen were seen as a new recurring foe. The costumes needed to be more practical in terms of maintenance and comfort for the actors inside. 11 were made in all. Only actors over 6 feet were hired.
• One of these is John Levene - who will become famous as Sergeant Benton of UNIT.
• The tube-joints are those plastic tennis balls which you used to get in schools.
• The voice derives from an unused Dalek idea - an electronic larynx. These are used by people who have had throat surgery. You hold it up to the palate. The device caused a resonance in the skull which made the speaker (in this case Peter Hawkins) suffer headaches and become nauseous. 
• The base-under-siege formula had worked well with The Tenth Planet, so something similar was dreamt up here - with the isolated complex being on the Moon as opposed to the South Pole.
• Frazer Hines was only known to be joining the TARDIS crew late in the day as the story developed, so that is why he is consigned to lying unconscious in the sick-bay for much of the first two episodes.
• Director Morris Barry was charged with gradually shortening Patrick Troughton's baggy trousers over the four episodes - just enough at a time that he wouldn't notice.
• French crewman Benoit's little onion-seller's cravat is not actually some kind of national stereotyping. The character's first name was changed after his ID badge prop had been made up - and the initial was now wrong.
• As Troughton familiarised himself with the Gravitron set prior to recording commencing, the prop collapsed and only narrowly missed him.
• With their obsessive preoccupation with the subject, it seems only right and proper that an Englishman should be in charge of the weather on Earth...