YMMV / Peril at End House

• Magnificent Bitch: Nick Buckley may not have been the worst criminal Poirot ever faced, but she was one of the only ones who ever manipulated him into actively helping her with her scheme. Faking a series of murder attempts on herself, Nick goads Poirot into thinking her life is in danger while disarmingly laughing off the suggestion and insisting that they were just silly accidents, as well as convincing all her friends of the danger, despite the fact that they had not previously believed her. Using this as a cover, Nick murders her cousin in such a way that Poirot will assume that she was killed in mistake for Nick; she then pretends that it was she, and not her identically named cousin, who was secretly engaged to the rich and recently deceased Michael Seton, setting herself up to inherit all his money. Nick had Poirot investigating every outlandish possibility save the real one until the very end; he ultimately found her out because of a letter that she could never have known that Maggie had sent her mother.
• Values Resonance: The Reveal that Freddie is a Recovered Addict with cocaine, explaining her physically abusive husband got her hooked and was mad when she left him to become clean. Everyone is sympathetic, especially when said husband shows up and attempts to shoot her and Poirot reassures her that her husband didn't kill Maggie. It's poignant that no one judges Freddie for her situation, and that she managed to get clean by sheer Heroic Willpower.
• The Woobie: Maggie Buckley, murdered as a result of mistaken identity. Or so everyone, including Poirot at first, thinks. In actual fact, it's worse, as Maggie was in fact killed by her cousin who then made everyone think that she had been the intended victim. And then pretended that Maggie's missing fiancé had actually been engaged to her, so that she could claim his fortune as the sole beneficiary of his will, thanks to her and Maggie having the same name and the engagement having been kept secret.

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