The series, by writer-producer David E. Kelley, stars Kathy Bates ( 'night, Mother) as lawyer Harriet "Harry" Korn who, this fall, will start taking on larger cases as her reputation rises.
Molina, who has signed on for a three-episode arc, will be one of Korn's clients, playing a murder suspect. Olivo joins the series when Korn needs additional help and hires a new "hotshot" lawyer.
Olivo took to the set July 11 to begin filming her role on the series. The performer won the Tony Award in 2009 for her performance in West Side Story and has also been seen on Broadway in In the Heights, Brooklyn and Rent.
Molina was nominated for the Tony for his performances in Art, Fiddler on the Roof and Red.
The second season of "Harry's Law" will kick off Sept. 21 at 9 PM ET. The series airs Wednesday nights on NBC.