Messing returns to the network home of Will & Grace as Julia Houston, a famed Broadway playwright who with the help of her writing partner, Tom (Christian Borle) pens the script for the Marilyn Monroe musical that's at the heart of Smash. Between the demands of staging a Broadway production, Julia is also looking to expand her family with husband Frank (Brian d'Arcy James) as the couple begins the adoption process.
Borle plays the openly gay Tom Levitt, the composer half of the Houston-Levitt team who is instantly drawn to the idea of a musical about Marilyn Monroe — until arrogant director Derek Wills' (Jack Davenport) name surfaces. He's often the voice of reason and compassion and general all-around good guy who fights for Megan Hilty's Ivy — who performs as Marilyn in the workshops — to land the lead when she goes head to head with Katharine McPhee's Karen.
Former American Idol runner-up McPhee stars as Karen Cartwright, an aspiring singer-actress fresh off the bus from Iowa as she pursues her Broadway dream. The morally grounded Karen will square off against Hilty's Ivy for the Marilyn part, facing professional and personal challenges and tests along the way.
Broadway veteran Hilty is Ivy Lynn, a longtime member of the ensemble who has yet to get her big break. After workshopping the lead in Tom and Julia's Marilyn play, she has playwright Tom in her corner as she competes against Broadway newbie Karen for the part. Also likely in her corner: womanizing director Derek.
Davenport's Derek Wills is one of Broadway's top director/choreographers — and he knows it. An ego for days, he clashes with playwright Tom about just about everything. Expect to see Derek challenge both Ivy and Karen as he pushes both acresses to their limits to see who's best cut out to play Marilyn.
Huston's Eileen Rand has a passion for her job — and throwing drinks in the face of her ex-husband, Jerry. Eileen is a longtime Broadway producer who got her start working with her husband and now faces worried clients and business associates worried that she isn't cut out to handle the business without Jerry — who has frozen her assets. Undeterred, she goes above and beyond to produce the Marilyn play — no matter the cost.
Cepero plays Ellis, Tom's over-eager assistant whose fascination with Marilyn plants the idea of a musical in both Tom and Julia's mind. He's smart and cunning — but can he be trusted?
Jaffrey plays Dev, Karen's smart, supportive and loyal boyfriend who also happens to work in the New York City Mayor's Office. Between his demanding job and Karen's Broadway dreams, their relationship will be tested as her career takes off.
James plays Frank, Julia's husband who grows restless after having sacrificed his career to see his wife succeed. Now that the couple's son, Leo, is in high school, Frank and Julia are stepping up their efforts to adopt a child. However, when Julia — who is supposed to be taking time off from work — comes home with plans to mount a new production, Frank isn't too keen on the whole Marilyn concept.