Hickory dickory dock by Agatha Christie

This book starts with Poirot in his London apartment, shocked that his super efficient secretary made three mistakes in a letter. Miss Lemon! She never make mistakes. Both Miss Lemon and George the butler are always so efficient and precise, perfect, impeccable.
He learns that Miss Lemon was thinking of her sister Mrs Hubbard, who is shaken due to a series of little thefts in the little hotel for students that she runs. Poirot talks to her and he's intrigued by the case, so he offers to look into it. Soon the thing becomes much more serious when a girl dies but the same Mrs Hubbard is able to reveal that the note left was not written by the poor dead Celia Austin, so it was not suicide, it was murder. (The night before Celia had put green ink in her pen).
Later Mrs Nicoletis, the hotel owner, a drunk woman, is killed and then Patrizia Lane too. Poirot and inspector Sharpe investigate. Poirot reveals a big drugs and precious stones smuggling business, lead by Valeria Hobhouse, Mrs Nicoletis' daughter. Opss I should have put a spoilers warning before that maybe. Oh well.
Students of all nationalities are in that hotel: Sally Finch is American, Genevieve and René French, Akibombo African, Elizabeth Johnston Jamaican. Len Bateson, Colin McNabb and Nigel Chapman should all be English, I think.
All the murders were by Nigel's hand, because they knew or saw something about it, so he killed them like he killed his mother years before.
I'm not too fond of this book. There are things I like, yes, and there's Poirot in it, which is always a good thing, but he has a relatively little role; the best part of the book is occupied by the students, and honestly I don't like them, and I can't understand why everyone gets always so angry when the police asks questions. There's been a murder, they have to, what's to be angry about, if they talk to everyone? There wasn't a single student I was fond of. Akibombo was the only one nice and good. The others were either too silly or too rude. Sally was ok but both Sally and Akibombo talked very, very little compared to all the others.
Little side note: Miss Lemon's name is Felicita :-) the irony :-)

Ita: Poirot si annoia