The Essence of Malice: A stylishly evocative historical whodunnit

Amory and Milo are holidaying in Italy, Milo is being his usual daredevil self and has taken up flying with his new friend Andre Duveau. Then he receives a disturbing letter from his former nanny, Madame Nanette, her new employer, Helios Belanger, has recently died of a heart attack only days after surviving a plane crash. Not only that, the formula for his new perfume has gone missing just days before the big launch party. Mr Belanger was the founder of the Belanger perfume business and was on the verge of launching a new fragrance. He is survived by three children, Anton the eldest who has the business brains, Cecile the middle child who inherited her father's skills with perfume, and Michel the wayward youngest child, always getting into trouble with married women, drinking and gambling. Of course Michel and Milo know each other, they've hung about together before! Helios had also married a much younger woman and they had a young daughter together. Can Amory and Milo uncover the truth about Helios' death and find the missing formula? This is book 4 in the series and Milo and Amory's marriage is still on a see-saw. It seems like every book starts with them being blissfully happy and then Milo starts going out and comes back at 4 am reeking of alcohol, smoke and stale perfume. He is evasive and refuses to give Amory straight answers about what he's doing , which always turns out to be totally innocent and related to the mystery. At this stage I feel it's getting a bit rinse and repeat, especially since it seems that Milo does more of the real detective work than Amory - or is it just that he always uncovers the clue that finds the murderer? Final gripe, and I'll try to be non-spoilery, Amory totally hits the TSTL button in the final chapters, just totally stupid behaviour. I still enjoyed reading this and I will read the rest of the books in the series but I am starting to feel that these are becoming a bit formulaic.