Thirty-fourth in the mystery series with Inspector Arnold and amateur detective Desmond Merrion.

Green was seriously put out. His daughter Iris had left home at half-past four to fetch her handbag, which she had left at Mrs. Whyttington's where she did part-time secretarial work, and here it was past six and she had not yet returned. Who was to get his tea, he'd like to know? But Iris would never get him a meal again, nor give reluctant help behind the counter in her father's chemist shop, for Iris was dead. Her body is found the next day floating in a sluice not far from her employer's house. It seems that in the October dusk she must have lost her footing on the narrow planking which bridged the sluice; and "accidental death" is the official verdict at the inquest. But when three months later Iris's successor as secretary to Mrs. Whyttington is found dead in most suspicious circumstances, and once again the situation becomes vacant, things begin to take on rather a different complexion and Scotland Yard is called in. It needs all Inspector Arnold's talent for patient plodding inquiry, assisted by the lively imagination and brilliant powers of deduction of his friend Desmond Merrion to solve a mystery that must surely be one of the most ingenious that Miles Burton has ever evolved for our entertainment.