《Holmes: The First Season of Basic Deduction Act》Ep5:The fifth episode
A number of patient deaths occurred in a hospital. The deceased were either physically weak or had an incurable disease. Although on the surface it seems that these people are normal deaths, Holmes does not think so. After careful examination of the body, he came to a conclusion: Someone pretending to be an "angel" helped these people to relieve their pain earlier in the hospital. They all died of murder. At the same time, Sherlock Holmes learned more about the truth of Watson's career as a surgeon.