The person responsible for the study:  Carney Landis, an American psychologist, conducted this experiment while he was a student at the University of Minnesota. 

Background information: Landis wanted to determine if human emotions could be associated with particular facial expressions. 

Methodology: Landis brought in an incredibly diverse group of participants, mostly from his local university, and then painted black lines on their faces. This was done to capture the movement of their facial muscles, especially in response to various stimuli ranging from disgust to pleasure. 

Results: Contrary to the hypothesis, there was no universal connection between stimuli and the corresponding facial expression in this experiment. In fact, at some moments, even the same individual would react differently to the same emotional trigger. The results of the study were incredibly misleading. 

Significance of results/legacy/recent relevance: While this experiment wasn't exactly successful in achieving its goal, it is widely known throughout the psychology community for its ethical concerns and controversial methods. The researcher, Landis, even went as far as to behead live rats in front of participants to "research" the resulting facial expression. Added to other ethical problems, this study harshly treated animals and broke many of the ethical guidelines that serve as the foundation for research today. 

How to improve the experiment: 

Adding on to the points mentioned in the past paragraph, this experiment could be improved by addressing the ethical guidelines, especially in the case of the harsh treatment of animals.