HBO’s salute to season two of “Girls” saw the sitcom’s lead quartet — Lena Dunham, Jemima Kirke, Allison Williams and Zosia Mamet — besieged by photogs and well-wishers at NYU’s Skirball Center, where three new episodes unspooled Jan. 9.

Big changes are evident. Williams, especially, has been flabbergasted by “the major change — all of it!” for her Marnie Michaels character. It’s why she’s up late certain nights.

“Scripts come to your inbox at midnight the night before the table read, and I always stay up and read them. Ferociously. For just this kind of thing,” Williams said.

For Andrew Rannells, season two is discovery time. “He realizes he’s actually gay,” Rannells said of his character’s failed attempt at heterosexuality. “Although Allison is a lovely person to try it with.”

As for the backlash that “Girls” is a lot of navel-gazing by privileged females, Dunham was not available to defend her show, but Williams, referring to a piece in the Los Angeles Times, came to the rescue: “As Lena said, anything that sparks a debate or conversation is inherently interesting or thought-provoking. There was a lot of praise lavished; that’s important and definitely met. But look at our world, no one agrees on everything.”

Added Rannells: “Most of that controversy worked itself out. Particularly with this second season, Lena, maybe not directly, addresses some of that.”