Brillstein Entertainment Partners has hired Stacy O’Neil to open the management/production company’s first full-service New York office.

O’Neil, who became available after the Firm partners Rick Yorn and Jeff Kwatinetz split to form new ventures, brings with her a client list that includes Amy Adams, Vin Diesel and Rachel Weisz.

O’Neil, who started her career as Stacy Boniello, spent eight years at the Firm. She started in the UTA mailroom and became a manager at Banner Entertainment before joining the Firm.

The move comes at a time when many entertainment companies are contracting. O’Neil will establish a Gotham office in January. Brillstein Entertainment hasn’t had a New York presence for years, after shuttering a short-lived book scout operation.

She rejoins Brillstein partner Aleen Keshishian, who left the Firm in 2005.

“I know from working side by side with Stacy how great it will be to have her creativity and vision in our company,” Keshishian said.

Brillstein chief exec Jon Liebman said the company has eyed New York, because many clients live there. O’Neil, who grew up in New Jersey, was eager to return East.

“So many great artists live and work there, and they are often overlooked,” Liebman said. “With all the changes and challenges in the entertainment business, we are lucky to have Stacy join our group of experienced talent managers and help us grow our business in New York.”