Sam Waterston is returning to the world of Law & Order.
The Law & Order alum, who played prosecutor Jack McCoy for 16 seasons on the flagship series, will guest-star on Law & Order: Special Victims Unit later this season, EW has learned.
Details on what brings McCoy back into the fold are being kept under wraps, but McCoy succeeded Benjamin Stone as executive ADA on the flagship series, and his son Peter Stone (Philip Winchester) is also set to appear on SVU this season, crossing over from the defunct Chicago Justice.
Law & Order: SVU will return Wednesday, Sept. 27 at 9 p.m. ET on NBC.
This article originally appeared on Ew.com