[Machine Translation] The second son of Osawa Noburo, a Urasenke professor, was poisoned to death in a thick tea ceremony hall. Nishida, a magazine editor who began covering the case, develops a faint crush on the suspect, Yuri Kannagi. In an attempt to get to the bottom of the string of poisonings, Nishida turns to Fumimon Onagata, a self-proclaimed "poison master" who is an eccentric and well versed in poisons. Onagata reveals the secret that the Osawa family has been hiding, along with the theory that "Sen no Rikyu = Christian".