Elementary
A Study in Charlotte
S4 E13:
Sherlock and Joan search for a murderer who used poisonous mushrooms to kill a botany professor and a group of the instructor's students. Also, when Joan is disturbed by loud noise next door, she discovers her neighbor, Trent (Richard Kind), is renting out his home through a vacation site that caters to hard pratiers.
Starring
Lee Aaron Rosen, Sarita Choudhury, Richard Kind