The incident happened around 2 a.m. on January 17, beginning when a woman rang a bell to gain entry to Inktastic Tattoo Parlor in Bedford-Stuyvesant.
After being buzzed in, two men entered, one armed with a gun and the other a knife, and the woman returned to their vehicle.
Police say one of the men raped a 23-year-old customer while the pair robbed everyone inside the store.
Authorities say they drove off in a Nissan Maxima.
The female rape victim was removed to Woodhull Hospital for treatment.
Anyone with information in regards to this incident is asked to call the NYPD's Crime Stoppers Hotline at 800-577-TIPS.