When Molly is having her hallucinogenic virus induced nightmare in "The Other Side" and about to enter the Carnival ride "final departure" which signifies her death, the guy working at the entrance says "Room For One More" This is a direct reference to the original Twilight Zone episode Twenty Two, where a woman is having nightmares and the lady on the elevator says Room For One More, taking her to Room 22 in the basement which is the morgue Great Twilight Zone episode to watch.
Jeffrey Dean Morgan (JD Richter) & Michael Gladis (Nate Malone) also worked together on episode 1.10, Lifeguard (2009), of The Good Wife (2009) as Jason Crouse & Mark Richardson respectively.