Sinister Errand — Peter Cheyney

Agent Michael Kells is in pursuit of Nazi spies in London, who have been tasked with the job of pinpointing the actual landing places of V1 bombs to improve their accuracy.

Through the strange byways of Kells's sinister errand flit the mysterious 'Auntie', the alluring Janine, the beautiful Mrs Vaile and the delightful and unfortunate Alison Fredericks.

'Nobody eats or sleeps in the course of this tale. And you probably won't either' New Yorker