"Mr. Hercule Poirot - you fancy yourself, don`t you, at solving mysteries that are too difficult for our poor thick-headed British police? Let us see, Mr. Clever Poirot, just how clever you can be". Was the anonymous note a brilliant challenge or a crackpot hoax? The answer is as loud and clear as a woman`s scream -precisely that of Alice Ascher, a shopkeeper in Andover bludgeoned to death on the job. Next to her corpse, a clue that`s as simple as ABC. Alphabetically speaking, the master Belgian sleuth suspects it`s now a matter of one down, twenty-five to