In the show's season finale episode, "Watershed," the body of a student was discovered in a hotel water tower.
"In Castle, the crime took place at the 'Cedric Hotel'—the real-life crime occurred at the Cecil Hotel in downtown Los Angeles, a similarly seedy establishment," writes LAist.
Another element lifted from the real-life case for the episode includes the use of footage from an elevator. In Lam's case, she can be seen acting strangely in the hotel elevator.
The episode does have some differences. The victim is a Harvard computer science student masquerading as a prostitute who was snooping on another guest of the hotel.