A Third Doctor and Jo novel in the Doctor Who series.
The beautiful village of Culverton is dominated by the presence of the local Aerodrome, closed by recent defence cuts. Spitfire veteran Captain Alec Bainbridge's disgust is appeased when he learns that the Aerodrome has been sold to a private concern, Legion International, which will operate civilian flights.
Then representatives of Legion International turn up in the village. Bainbridge distrusts the newcomers at once - smiling and eerily beautiful in their sleek black uniforms. The rest of the village, however, seems to fall quickly under their sway. More worryingly, Legion International's personnel begin to patrol the village, promising to stamp out unruly or unsavoury elements. Bainbridge is alarmed by their similarities to the Nazis that he gave his best years to defeat.
When several locals disappear, and Bainbridge witnesses black-uniformed troops unloading ominous, coffin-like containers from the hangars, he contacts his old friend the Brigadier who promises to investigate. When his superiors refuse to help, the Brigadier asks the Doctor and Jo if they could pay a visit to Culverton to find out what's really going on behind Legion International's facade . . .