The 37-year-old 'Star Trek Into Darkness' actor has signed on to appear in at least one of 'Girls' season four episodes, but HBO has not yet released any character details, reported Us magazine.
Quinto was photographed shooting scenes for the award-winning HBO series in New York City earlier in the week.
The actor has worked extensively in television in the hit dramas 'American Horror Story', '24' and 'Heroes' in years past.
Lena Dunham, Allison Williams, Jemima Kirke and Zosia Mamet are returning as the core cast for the new 'Girls' episodes.