The Charming Quirks of Others is the seventh book in The Sunday Philosophy Club Series by Alexander McCall Smith.

[1] Isabel Dalhousie is approached by the wife of a trustee of a prestigious Scottish school concerning a poison pen letter that her husband, a trustee of said school, has received, concerning one of the candidates for the post of headmaster.

[2] Isabel's nieces, Cat, has a new boyfriend who is, coincidentally, one of the candidates for the aforementioned position.

[3] Isabel works in her usual manner to get to the bottom of the mystery.

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