'Smash': Julia and Michael Can't Deny Their 'History' (Exclusive Video)

The duo's chemistry creates one of the most uncomfortable rehearsals yet on the NBC Broadway drama.
"Smash's" Will Chase and Debra Messing

Smash may soon need to come with a Rent-like diagram mapping out the love lives of its sprawling cast.

After playwright Julia (Debra Messing) and Michael (Will Chase) shared a not-so-secret kiss, the duo's chemistry begins to get in the way of the Marilyn Monroe musical at the center of the NBC Broadway drama.

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In a clip from Monday's episode -- fittingly titled "Chemistry -- Michael has a hard time staying in character as Joe DiMaggio during rehearsals with Megan Hilty's Ivy, who either is over-acting as Marilyn or who may have eyes for her new co-star.

Confused yet? Check out the clip, exclusive to The Hollywood Reporter, to see everyone struggle to get through a reprise of "History Is Made at Night" and preview the chemistry overload coming from friends Julia and Tom (Christian Borle), co-stars Ivy and Michael as well as former adulterers Julia and Michael. Oh, and Ellis (Jaime Cepero) seems to have found a new pal in Anjelica Huston's Eileen.

Who do you think has the most chemistry? Smash airs Mondays at 10 p.m. on NBC.

Email: Lesley.Goldberg@thr.com; Twitter: @Snoodit