Smash First Look: Watch Katharine McPhee Transform Into Marilyn Monroe With a Sexy Mambo!

SmashWill Hart/NBC

News flash: Katharine McPhee is not ugly. Nor untalented. And when you see her transform into Marilyn Monroe in the next episode of NBC's Smash, well, your TV crush (can we call it "McPheever"?) will be in full effect!

We just scored an exclusive first look at Katharine's stunning performance of "20th Century Fox Mambo" in episode two of Smash, airing this Sunday...

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In this first look at "Callbacks," Karen (McPhee) is throwing herself into winning the part of Marilyn, and we get to reap the rewards of her hard work. What starts out as a rehearsal for the number "20th Century Fox Mambo," turns into Karen transforming into the blond bombshell.

It's so hard to pick between Karen and Ivy (Megan Hilty) for the lead role, and this clip will only make it harder for you. Check out the original number and tell us who you think should win the part of Marilyn Monroe!

Smash airs Monday nights on NBC. (NBC and E! are part of the same NBC Universal family).

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