Literature: Cat Among the Pigeons  Cat Among the Pigeons is a
1959 mystery novel by Agatha Christie.  At the start of the
summer term at Meadowbank School for Girls, a prestigious prep
school in England, there is no reason for Miss Bulstrode, the
popular but aging headmistress, to believe that the challenges
facing her will be more than the occasional irate or inebriated
parent. She scarcely listens when Mrs Upjohn, a parent,
recognizes someone that she sees from her wartime days in the
intelligence service. But there is a killer at the school who
does not wait long to strike.  Cat Among the Pigeons contains
examples of the following tropes:    • Adaptational Villainy: In
the book Miss Springer is a comparatively innocuous character;
in the Poirot adaptation, she becomes a nasty sadist and an
Asshole Victim.   • Blackmail: Miss Blanche. It gets her killed,
just like all of Christie's other blackmailers.   • Boarding
School   • Cool Teacher: Honoria Bulstrode, headmistress of
Meadowbanks, is not overly strict,