The Big Four: A Hercule Poirot Mystery (Mystery Masters) by Agatha Christie details from bookadda

When a man collapses at Poirot's door, he implicates a vicious international organization called the Big Four. Left in the care of Poirot's landlady, the man dies, and the dapper sleuth realizes this crime may be a deadly diversion. Poirot and his pal Captain Hastings are soon plunged into a complex case full of deception as they themselves dodge death. But do they really avoid the Grim Reaper? Hastings isn't sure when he's invited to Poirot's funeral. Reader Hugh Fraser captures Christie's "cozy mystery" world with his usual panache. This is the 24th title in the Agatha Christie Mystery Masters series, deemed the Best Mystery Series of the 20th Century at Bouchercon, the world's largest mystery convention (held annually). Eccentric and fastidious, egocentric and precise, the little Belgian detective with his sparkling eyes and carefully waxed moustache looks, to the uninitiated, ridiculous. Yet he is one of the most popular characters in all of literature Plump, barely over five feet, four inches tall, the vain Poirot is nevertheless eternally dignified, and always wears formal clothes, down to gleaming white spats and up to his jaunty bowler. He solves murders using, as he insists, nothing but his little grey cells.