Doctor Who: EVERY Version Of The Cybermen Explained

20. Mondasian Cybermen (First Appearance: 1966)

The first Cybermen encountered by the Doctor originated on Earth’s twin planet Mondas.

Aeons ago, Mondas drifted away from Earth to the very edges of space. Realising that its inhabitants were growing weaker, Mondas' scientists and doctors created spare parts for their bodies, in order to 'improve' them. Over time, they were completely replaced by metal and machinery. Emotions were removed. The Cybermen were born.

In 1986, a dying Mondas drifted closer to the Earth, so the Cybermen attempted to use Earth’s energy to replenish it. But the First Doctor foiled their plans, resulting in Mondas’ destruction.

Following this, the Cybermen became even more fixated on Earth, plotting to sabotage its weather and steal its minerals, before carrying out a full-scale invasion.

They also spread throughout the universe, colonising another planet, Telos, and establishing a base there after wiping out the indigenous Cryons. Another strain of Mondasian Cybermen evolved on a colony ship, as part of Operation Exodus.

Reflecting the fact that they were merely humanoids who had upgraded their bodies with spare parts, the earliest Cybermen were fairly primitive – their faces covered with cloth, their bodies covered in surgical sheeting, and their hands exposed.

Over time, they did become more sophisticated, like the Cybermen encountered by the Second Doctor on Telos, whose faces were now complete metal and had sleeker, sturdier bodysuits.

Though built for survival, these Cybermen weren’t unstoppable, with their weaknesses including radiation and the "Polly Cocktail", a chemical mixture that attacked the plastic components of the Cybermans' machinery.