The 13-episode series from "Friends" creator Marta Kauffman will debut in 2015. Fonda and Tomlin will play Grace and Frankie, respectively, nemeses whose lives are turned upside down and inadvertently intertwined when their husbands come out of the closet and announce that they're getting married to each other.
Kauffman and Howard J. Morris are co-writing the series that they will executive produce along with Fonda, Tomlin, Paula Weinstein, David Ellison, Dana Goldberg and Marcy Ross.
Fonda last appeared on Broadway in the 2009 drama 33 Variations, for which she garnered her second Tony Award nomination, following There Was a Little Girl in 1960. A two-time Academy Award winner for "Coming Home" and "Klute," she also received an Emmy Award nomination for the Aaron Sorkin drama "Newsroom."