The Butler, Scattering into Smoke is Chapter 171 of the Kuroshitsuji manga.
Summary[]
Baldroy believes the five people in protective clothing to be armed soldiers and that he and Lau have already been found out. When the "first unit" is commanded to move forward, Baldroy is about to take out his gun, ready to fight back, but then, he and Lau are only showered with bleach. They are quite stunned; however, before they can process what happened, they are hit by the "second unit" with disinfectant. Afterward, Lau and Baldroy are also sterilized and sanitized by the people in the protective suits.
When the team is done and Lau and Baldroy have been thoroughly cleaned, Baldroy asks why they did that. One of the people in the protective suits takes off her helmet and informs Baldroy that pathogens are not allowed in the Athena Sanatorium. Baldroy is shocked that it was a woman under the suit, and when one of the woman's colleagues hands her a mask and addresses her as "chief nurse," Lau realizes that this woman is the "Miracle Healer" everyone is talking about.
The chief nurse Ada does not like it that the success of Athena Sanatorium is attributed to a "miracle" as it trivializes the nurses' hard work and use of strict hygiene management and statistics. Ada's colleagues agree and state that they immediately eliminate every bacterium that enters the sanatorium.
Then, Ronald Knox, posing as a doctor, enters the room, greets Ada, and announces that he is the physician in charge of "Mr. Burgh."