Dushku's character, a savvy lawyer named J.P. Nunnelly who leads the best criminal defense firm in New York, will be introduced in the episode airing Tuesday, May 9, when she is hired by Dr. Jason Bull (Michael Weatherly) as one of his employees is heading to prison (!).
There's no word yet on whether Dushku will be sticking around as a series regular or whether her character will appear in just a few episodes towards the end of the season.
Earlier today, Bull was renewed for a second season, and will be helmed by a new showrunner.
Bull airs Tuesdays at 9/8c on CBS.
(Full disclosure: TVGuide.com is owned by CBS.)