Nazanin Boniadi, Neil Patrick Harris

Who was Nazanin Boniadi's childhood crush? None other than Neil Patrick Harris.

"I've loved him since I was little. I'm not even joking! I've had a crush on him forever," she tells TVGuide.com. "So to be playing his girlfriend now is surreal."

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When Boniadi landed the part of Nora on How I Met Your Mother last year, little did she know that it would lead to a recurring gig with no end in sight for now — she has "no clue" how many episodes she'll be in this season — never mind the fact that Nora, and not Robin (Cobie Smulders), would be the one to force Barney (Harris) to reevaluate his womanizing lifestyle.

"In real life, too, women love to be that girl who tames the bad boy," Boniadi says. "It's always fun to play that character, especially with Barney Stinson, who's so beloved. You get to act opposite Neil. He's phenomenal. He raises everybody's game. To work opposite him, you have to be at your best and you become better and better as you work with him."

The General Hospital alum got a crash course in slapstick acting — a Harris forte — on Monday's episode when Barney and Nora's planned romantic evening goes horribly wrong. Among the mishaps: a rodent lands on her head, she loses a tooth ice-skating, and a guy seemingly commits suicide off Barney's building. "The hilarity that ensues on the streets of New York is priceless," she says. "You'll see some of the date indoors, some outdoors. But no matter where we are, something kills the mood. I can tell you I've never had to do this much physical comedy in any of the episodes I've done so far. It was a fun challenge for me."

Check out photos from How I Met Your Mother

Further complicating the evening is Robin's therapist-turned-beau Kevin (Kal Penn) suggesting that people choose significant others who remind them of their parents. That brings Lily's dad (Chris Elliott), Barney's mom (Frances Conroy), Ted's mom (Christine Rose) and even Marshall's late dad (Bill Fagerbakke) back into the fold. (Barney's brother, James, played by Wayne Brady, also returns and meets Nora.) "It was so cool to have everyone there. Frances Conroy — brilliant, brilliant actress. I adore her, and to work with her and Kal Penn and Wayne Brady, who I also love, with the Fab Five, as I call [the regular cast], was icing on the cake," Boniadi says. "But the whole thing is a little Oedipal. You can just think about that theory and see how that can spoil anything."

The intended date is yet another effort of Barney's to prove that he is a changed man and is serious about Nora and being in a committed relationship. But does a busted evening bode well for their future, especially with Robin secretly aching over Barney?

"Not to give too much away, but [relationships] are about dealing with tough times and good ones. They both definitely feel something for each other and the timing has been right for them to date now," Boniadi says. "I think, very much like Robin, Nora's very strong-willed and Barney needs to be whipped into shape. He's definitely dated a lot of women and I think that's why his friendship with Robin is so great because Robin doesn't take any of that laying down. That's why the interplay between those characters is fun. Nora has some of that too and that's the dynamic that some people have liked with them, although there are obviously big differences between Robin and Nora as well."

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Boniadi does not know when Robin's true feelings will be revealed to the rest of the group, but she is looking forward to it seeing it play out. Robin and Nora, of course, are the top two candidates for Barney's mystery bride, the identity of whom will be unveiled (no pun intended) before season's end. Like any other Mother fan, Boniadi is well aware of the Barney-Robin 'shippers out there — and no, she does not hold anything against them.

"Obviously, playing her, I want Barney and Nora to be together," she says. "But as a fan of the show, there's always something to be said about two series regular who you've watched for six seasons find happiness with each other. I'm kind of torn.

"Whatever happens," she continues, "you have to find a good place to play that, whether they end up together or they don't or who ends up with whom. At the end of the day, it's a sitcom and it should all be fun, so I'm excited just as anyone else to see it all unfold."

How I Met Your Mother airs Mondays at 8/7c on CBS.