Jonathan Groff: For the complex, linchpin role of "Jeff," a thoughtful, ambitious yet immature recent college graduate driven by his desires to act in unthinkable ways, Jonathan Groff infuses his character with energy, vulnerability, intelligence and provocative sexuality - just some of the qualities that have already marked him one of the true talents of his generation. Jonathan Groff is quickly emerging as one of the most exciting young talents in the industry. He has joined the cast of the critically-praised hit series,GLEEas the lead male vocalist of the rival glee club, Vocal Adrenaline, as well as being a potential love interest for Lea Michele's character, Rachel.Portia Reiners: Tackling the role of "Mel," the restless, selfish, and seductive object of Jeff's unrequited affections, Portia Reiners brings honesty, humor and a bold magnetism to the screen. The young actress comes toTWELVE THIRTYafter a string of well-received performances on stage, television and film. Reiners began her acting career at seven in a production ofOliverand continued working in theater until the age of ten when she made her first television appearance on ABC'sAll My Children,one of America's most popular daytime series.In the pivotal role of "Maura," Mel's timid, embittered, virginal older sister, award-winning young actress Mamie Gummer inhabits her character's violent coming of age with depth and dignity. Born in 1983, Mary Willa "Mamie" Gummer is the eldest daughter of Academy Award-winning actress Meryl Streep and renowned sculptor Don Gummer. But, in the short span since her 2005 graduation from Northwest University, Gummer has already made a distinct name for herself as a talented and versatile actress, performing on stage, television and screen to rave reviews and numerous awards.Karen Young: Playing the role of "Vivien," Mel and Maura's mother, Karen Young brings wry humor and deep empathy to a woman struggling with a carefree independent streak that has consistently clashed with her role as wife and mother. An actress of range, nuance and beauty, Karen Young has created interesting roles in both independent and big-studio films, television and theater for the past 25 years. She made her film debut in 1983, with a starring role inHandgun,and has since amassed credits in over two dozen feature films, among themJoe the King, Torch Song Trilogy, Criminal Lawwith Gary Oldman andDaylightwith Sylvester Stallone. Of particular note was her critically hailed 2005 performance in Laurent Cantet'sVers le Sud(Heading South) co-starring Charlotte Rampling.Reed Birney: In the role of "Martin," Mel and Maura's genial estranged father, Reed Birney encompasses all the pleasures and regrets of a man who couldn't embrace his true self until middle-age, leaving his daughters and ex-wife to deal with the fall-out. Born in 1954 in Alexandria, Virginia, Birney is known for his splendid dramatic work in a variety of roles on stage, television and screen. Perhaps most recognizable from roles on the NBC seriesKings, Law & Order: CI, Law & Order: SVU, HBO'sFrom the Earth to the Moonand the popular CW showGossip Girl,his talent and versatility has captivated audiences for over 30 years.