"Hey, Mouse, play us something," one of the mechanics called from the bar. And then the murders began.
Samuel R. Delany, Nova
It was seven o’clock of a very warm evening in the Seeonee hills when Father Wolf woke up from his day’s rest, scratched himself, yawned, and spread out his paws one after the other to get rid of the sleepy feeling in their tips. And then the murders began.
Rudyard Kipling, The Jungle Book
(I see somebody already beat me to it with this one. Oh, well.)
The Report Begins: One afternoon early in a certain January, the weather showed a lack of character. There was no frost or wind; the trees in the garden did not stir. There was no rain, although anybody accustomed to predicting rain might have forecast it with a fair expectation of being right before nightfall. Cloud lay thickly over the sky. The face of the sun was not visible. Consequently, shadows had no form. And then the murders began.
Brian Aldiss, Report on Probability A
The particular ill-will between the men of the Household of Hobar and the Sixlimbed Folk was said to date from the time of the Hennan Hobar who was the senior of the cadet line which inherited - for lack of male heir in the elder branch - all the fat lands of the household, well-girthed in appleyards. And then the murders began.
Avram Davidson, The Island Under the Earth