In the novel The Secret Adversary, Astley Priors is the home of Dr Adams. The house is located in the village of Gatehouse, Kent.
Astley Priors is a "pleasant redbrick edifice", and is surrounded by well-wooded grounds. The house is not observable from the road, because of the surrounding woods.
Tuppence and Jane Finn are held at Astley Priors by the gang. Julius Hersheimmer later manipulates Kramenin into taking him there, to rescue the girls.
At the end of the novel, the gang has fled from Astley Priors in a panic, leaving behind "various damaging documents which compromised them hopelessly".