The pictures from set, and a helpful confirmation from HBO, confirm Zachary Quinto will guest star in season 4 of Girls.

“Ask Me My Name!” Viewers of the HBO comedy Girls certainly do not need to ask Zachary Quinto for his name, but they may ask what he is doing wearing that smock. Confirmed this morning, Zachary Quinto is on the Bushwick set of Girls filming a guest spot alongside Lena Dunham.

In his Instagram photos from last night you can see the smock and the “hipster background action” from his time on the set.

What could Hannah be up to dabbling in volunteer work in Brooklyn? Most likely looking for an excuse to add an uplifting selfless story to her personal memoir, but the possibility she did not choose to be there is also likely. The photos taken on set caught the group at craft services still in their aprons between takes.

There is no word on how many episodes Quinto is set to appear in during season 4. Other guest stars set to appear next winter include Community‘s Gillian Jacobs as Mimi-Rose Howard and Parenthood‘s Jason Ritter. Jacob’s role is confirmed to be part of a multi-episode arc beginning with episode 5, titled, “Mimi-Rose.”

Girls is well into filming season 4 already and it looks as if all the regulars, including Andrew Rannells, are slated to play out the next chapters of their stories. Lena Dunham and Jemima Kirke were both spotted on set along with Quinto, but their scenes are not confirmed to be together as a trio.

Thanks, TVLine.

Girls returns to HBO in January 2015.