The Insider.com

On a show revolving around the production of a new musical and the two Broadway babies duking it out to claim its leading role, you might not suspect that much time is dedicated to the office politics the star's boyfriend endures.

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But Smash has given lots of screentime to Dev's work-life the last few weeks -- and according to star Raza Jaffrey, there's good reason for that. In addition to finding out what lies ahead thanks to Dev's late nights at the office, Raza revealed how an upcoming musical moments brings every character together for the first time.

Insider.com: You and Katharine McPhee share some great chemistry -- how much time did you two spend together beforehand to build that?
Raza Jaffrey: Not much, actually. You never know when you turn up on set the first day what it's going to be like when you have to be romantic with another actor -- it's always a risk that you'll be coming from the same emotional place, but thankfully Kat and I see this relationship very similarly. She's an extraordinary performer with such a natural quality. That really makes our scenes easier to do. It's always so nice when chemistry works out and people sense that – plus, there's some properly juicy stuff coming up before the end of the season that I think people will be very surprised by.

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Insider: Oh really? Are you referring to Dev and R.J. perhaps?
Raza: Well ... people are expecting a certain thing to happen there. I know there's already been talk of Dev cheating on Karen because of R.J. [played by Tala Ashe], but I will say that you should expect the unexpected. It's not necessarily going to be what you think.

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Insider: He doesn't really strike me as a cheater.
Raza: Yea, he adores his girlfriend; only wants her to do fantastically well. But whether that's the right thing for their relationship, you'll just have to wait and see.

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Insider: Now, you have a big musical background, right?
Raza: I do. I played Sky in Mamma Mia when that opened and used to do a lot of musicals in London. But when I signed on to do this, Dev wasn't supposed to be a singing character. However, the writers decided to throw him a song. I thought it would be a little number but it's rather large. It ended up being the biggest production we've done to date and that comes in episode 12. It's an amazing, original number written by Marc [Shaiman] and Scott [Wittman] that was such great fun.

Insider: What can you tell me about the song?
Raza: With what the song is saying, it ends up being a culmination for a lot of storylines. Although Karen and Dev are what sparks the song on, it ends up being a giant company number and says something kind of great about us all being in this together. It turns into a celebratory number. I think it'll turn a few heads. That's for sure.

Insider: Looking forward, who have you not gotten to work with yet that you'd like to have a scene with next season?
Raza: Well, because of that musical number, I've worked with the whole cast now. Plus, the storylines all start meeting as we get closer and closer to the finale. So, I'd just like more of that please. I do find it hard to do any scenes with Jack Davenport, however, because he makes me laugh so much. But I adore him – it's nice to have another Brit on the show. He gets my jokes [laughs].

Insider: Speaking of the finale, what are you excited for people to see?
Raza: Without giving too much away about what's to come in the end of the season, there's some really meaty, meaty stuff about to happen with Karen & Dev – it's been just a treat to play that heft. It would be easy to have Dev be two-dimensional – just the boyfriend waiting at home for his girlfriend. But I think from the start the creators have done a great job about making all the characters people you care about. I'm delighted that I signed up for a character that has been fleshed out so wonderfully, so I would just hope for more of that please.

Insider: Lastly, since everyone has an opinion, what's your take on Ellis?
Raza: He's a piece of work, isn't he? I think as time goes on, the reasons behind all the horrible things he's doing will be revealed more and more. But it's good to have characters people love to hate. Right?

Smash airs Mondays at 10 p.m. on NBC.