In the short story The Shadow on the Glass, Inspector Winkfield is the investigating officer who turns up at the party hosted by the Unkertons at Greenway's House to investigate the shooting of Moira Scott and Captain Jimmy Allenson. After questioning the various witnesses, he comes to the conclusion that only Iris Staverton could have done it. He therefore did not welcome the arrival of Harley Quin whom Mr Satterthwaite said could help elucidate what had happened. Nonetheless he did not object to listening to Quin's inputs.
Winkfield is described as "a shrewd-looing forceful man of forty odd.
In the short story The Bird with the Broken Wing, Inspector Winkfield is again the investigating officer, this time at the death of Mabelle Annesley at Laidell. When he sees Mr Satterthwaite there, he seeks him out privately. he recalls Satterthwaite's help with the case of "Mrs Strangeways" (no such person?). Winkfield asks for his help again. He says that Satterthwaite has an entre with the people at the house and that he has "a flair for that sort of thing".