B is for... Bannermen

A humanoid mercenary group of obscure origins. They were led by Gavrok, and embarked on a genocidal mission to totally eliminate a race called the Chimerons. It is unclear whether this was on their own initiative, or if they were in the pay of some other power.
They dressed entirely in black, and ordinary soldiers wore narrow-lensed eye-wear. They decorated their uniforms with black and red banners - hence their name. Though appearing identical to Earth people, they had bright red tongues. and had gnarled, claw-like hands.
Their ruthlessness was notorious, as the Navarino tourists trapped on Earth in 1959 knew of them and feared them. These tourists had arrived at a holiday camp in South Wales, and had amongst them a Chimeron princess - Delta. She had an egg with her. Determined to eradicate her, Gavrok murdered the Toll-Keeper at the spaceport after he had told him where the group were going, then gave chase. He made use of an informer to locate their exact position - eliminating him afterwards, rather than pay a reward.
It transpired that the Bannermen were highly susceptible to the high pitched singing of Chimeron children. When the egg hatched into a young Chimeron female, the Doctor arranged for her singing to be amplified to overpower the mercenaries, whilst Gavrok was killed after stumbling into one of his own traps.
The Bannermen were taken captive, transported in their own ship by Delta and local lad Billy, who had decided to transform himself into a Chimeron so that he could be with her and raise the child. The Bannermen would be taken to some unspecified authority for punishment for their genocidal crimes.

Played by: Don Henderson (Gavrok). Appearances: Delta and the Bannermen (1987).

• The story title - and hence the name for these characters - was inspired by the group Echo and the Bunnymen.
• Another inspiration was Akira Kurosawa's Ran, a 1985 film in which Shakespeare's King Lear gets the Samurai treatment. In this, the King has troublesome sons rather than daughters, and their forces wear different coloured banners to indicate their particular allegiance.
• The Bannerman helmets mark the final appearance of costume elements first seen in Earthshock back in 1982. They were also worn by the Train Guards in The Mysterious Planet in the previous season.