Jezaille Brett's research report was evidence in the trial of Ryunosuke Naruhodo for the murder of John Wilson. It contained the research materials that Brett had collected on the deadly substance known as curare. There were three sections: the synopsis, the special characteristics, and the practical applications. The report had information about the effects the poison would have on the body if it entered into contact with the blood, like muscle paralysis that would lead to death by suffocation. There was also information about South American indigenous tribes using it to hunt.
An unknown poison[]
- Main article: The Adventure of the Great Departure
Wilson arranged a lunch meeting with Brett, who was one of his students, at the restaurant La Carneval on November 22. Due to an appointment for a tooth extraction at 1 p.m. that day, the lunch was set to 2 p.m., and only Brett would order food. Unbeknownst to Wilson, Brett would use this opportunity to assassinate him without leaving a trace, using curare. This toxin was unknown to investigators in Japan at the time. Brett laced a bottle of carbonated water with the poison. From her research, she knew that the poison was harmless if ingested orally, but Wilson's tooth extraction provided a way for the poison to bypass the digestive system and travel to the bloodstream, and she took advantage of this fact.
During Naruhodo's trial, during a recess to call Brett to the stand, Yujin Mikotoba instructed Susato Mikotoba to bring Brett's research report to the trial. Naruhodo accused Brett of poisoning the water. Although no poison was detected on the bottle, Susato managed to deliver the report. In an attempt to "disprove" Naruhodo's accusation, she drank the remaining water in the bottle, knowing that it would not harm her. However, Mikotoba's translation notes on Brett's report allowed Naruhodo to uncover how only Wilson could have been affected by drinking the poisoned water.