bomb
Scully: "Mulder its me."
Mulder: "Where are you Scully?"
Scully: "I'm on the roof."
Mulder: "Did you find anything?"
Scully: "No, I haven't."
Mulder: "Whats wrong?"
Scully: "Well, I just climbed up twelve floors. I'm hot, I'm thirsty, and to be honest, I'm wondering what I'm doing up here."
Mulder: "You're looking for a bomb!"
Scully: "Yes, I know that. But the threat was called in to the Federal building across the street."
Mulder: "I think they have that covered."