When Alexis goes undercover at Hudson University, she uses "Clara" as an alias. She used the same alias just two episodes previous, in "XY (2015)", taking it from a character in one of her father's Derrick Storm novels.
The plot of this episode was inspired, in part, by the 1971 Stanford prison experiment.
The Castle Depression Rescue Kit contains Sumatran civet coffee beans. The Asian Palm Civet is a cat like animal that reputedly eats the berries of the coffee plant, digesting and fermenting the berries and pooping out the coffee beans. Those poop beans are considered the best coffee in the world and sell for about $300./pound.