Zosia Mamet says things can get steamy on the set of "Girls," which is currently shooting. "We can never have an air conditioner on during filming" on location because of the noise, she told Confidenti@l at the premiere of "The True Cost." "It gets really personal with a crew of 75 humans in whatever small room with no air conditioner." But it seems that a little olfactory discomfort is no biggie for Mamet: "It's been five years, and we're all like family."