Expert Tailoring NYC

Hi! In search of an expert tailoring service in NYC. Bought a custom gown online as my second-look that is stunning, but just a tad big. I don't want to risk it and go to my every day corner seamstress... looking for a high-end expert tailor. Don't have much time - about 3 weeks, but should be enough time to pay for expedited service! Anywhere in Manhattan! Thank you!