[Nicotine, pesticides, and tobacco, in Three Act Tragedy]

Since one of the main characters in Three Act Tragedy was an actor, the three murders described in the book have been likened to a curtain. The three seemingly unrelated murders were connected at the end of the story, a thrill unique to the author, Agatha Christie. Nicotine was used in all three murders in this book. Nicotine is highly toxic and was one of the main pesticides used until the mid-20th century. Although its use is currently prohibited, neonicotinoid pesticides, which have reduced toxicity, are still being used. Problems with nicotine intoxication include accidental ingestion by young children, green tobacco sickness, and suicide attempts. When nicotine enters the body, it binds to acetylcholine receptors and causes various symptoms.