Murder Must Advertise
Sayers herself worked at an advertising agency, and the book is filled with the minute detail that only an insider would know -- the feuds between copywriters and the art department, the irritating clients who think they know best, the row of errand boys playing with yo-yos and catapults while they wait to be sent out on jobs. Peter Wimsey slots into this milieu as if he were born to the job, naturally.
I think it's around this time that Sayers really began to fall in love with her own hero, because Wimsey is too good to be true. A brilliant mind, an exceptional cricketer (with the 'exceedingly characteristic late cut' quoted by Nicola Marlow in The Cricket Term) and also (urgh) at forty-five, mind you, diving from the tops of fountains in a harlequin outfit. Now that is where I draw the line, I'm afraid.
These quibbles aside, and the odd regrettable hint of casual racism, Murder Must Advertise is a great romp which I raced through much more quickly than I planned.