A London-based newspaperman is about to head for Paris for his first vacation in three years when he becomes embroiled by the murder of a shopkeeper in the square where he lives, followed shortly afterwards by the shooting of a police constable.
Working alongside Inspector Jefferson of Scotland Yard he encounters a spirited socialite when he accosts her family's butler whom he wrongly suspects is the killer. Public alarm rises further when a barmaid at a nearby pub is also killed.