The movie that Rachel and Mark are watching at the beginning of the episode is "Attack of the Killer Tomatoes". One of George Clooney's (Doug Ross) first roles was in "Return of the Killer Tomatoes"
This episode's rather cryptic title refers to the Nile, as in "in denial". Several characters in this episode are in that predicament - the rapper who is secretly having sex with his male friend and insists that he's not gay even when he gets diagnosed with HIV, and Kerry Weaver who is forced to confront her true feelings about firefighter Sandy Lopez (Lisa Vidal).