Ever since Siobhan Smythe was recruited by Cat Grant for an assistant position at CatCorp, "Supergirl" viewers have been eagerly anticipating her transformation into the ruthless Silver Banshee. Tonight, the wait is over when actress Italia Ricci adopts the villain's distinctive black and white look, teams with Livewire and prepares to scream bloody murder at Kara Zor-El and her new friend and ally, the dimension-tossed Flash.

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In last week's episode, an intoxicated and frustrated Siobhan stumbled off a rooftop balcony, only barely saving herself from going splat when her supernatural scream kicked in and broke the fall. Tonight, Siobhan finally takes on the identity of Silver Banshee and utilizes her newfound powers to exact revenge on those standing in her way -- even if that means taking down Supergirl and the Flash in the process.

Ahead of tonight's big crossover episode, Ricci spoke with CBR News about tangling with superheroes, learning how to be the meanest supervillain she can be from fellow Supergirl nemesis Livewire, and whether Silver Banshee will be heard from again following her debut in the anticipated crossover episode.

CBR News: How cool is it being the big villain in the Supergirl/Flash crossover?

Italia Ricci: I didn't know that going into it. I read it and I was like, "Oh, my God!" I'm so excited; it's such a huge episode to read. I can't imagine what it's going to look like.

Silver Banshee's abilities only recently manifested. What can we expect from her during this confrontation?

Siobhan has superhuman strength. You'll see a bit of that. You are obviously going to see her scream. She doesn't know how to be a villain. She has this new power now. She's trying to figure out how and why she's using them. Siobhan looks to Livewire as inspiration. Livewire takes Siobhan under her wing and shows Siobhan how to be bad and how much fun it can be.

When we last spoke, Siobhan hadn't transformed into Silver Banshee. How did the makeup process evolve to arrive at her current appearance?

We had three separate hair and makeup tests. The first look was quite a bit different than what she ended up looking like. It was more of a kabuki-face paint thing. Then it was a long black and white wig. It was very full. It was almost sort of Tim Burton-y. They wanted to add prosthetics, so I went and got fitted. Then we did another test and another test. Originally, she slowly turns into Silver Banshee and then that's her permanent form. But, they wanted to keep the option open of her turning into Siobhan. Livewire sort of creates this look for her. We wanted it to be something she puts on.

What else can you tease about tonight's episode?

I don't know. We shot so much. Even in the episodes I've seen air already, there's so much more than I remember. I can say last week had one of my favorite moments on set ever. At the end of the episode, Siobhan falls off of a roof and she screams really loud. Her scream saves her and that's what unlocks the curse. They actually let me do the fall. They lifted me up in a harness, about 60-feet and let me scream my face off and fall off the side of a building on the back lot. It was amazing. I had so much fun.

How raw was your voice by the end?

I screamed for the first one, just so I could get a sense of how my face would contort. I'm sure they are doing the screams in post because they've got to be super-sonic. The first time I screamed, it was exhausting because it was such a long drop that I ran out of voice. I had to stop screaming, inhale, and keep screaming.

Siobhan has developed a personal connection with Winn. In what ways will that be touched on?

You will see more of her and Winn, whether you like it or not.

They're a bit of an odd couple.

I remember reading those earlier scenes and I was like, "What? That came out of left field." But, as I spent more time in Siobhan's shoes, I was like, "I kind of love that." It humanizes her a little bit more than just being the bad seed at the office. It gave the fans something to root for because nobody is going, "Oh, we hope she turns nice." That was her saving grace.

You recently completed the pilot for this fall's "Designated Survivor" TV series. Does that mean the first appearance will also be Silver Banshee's final appearance?

I hope I get to come back. If they will have me, I'm happy to go back.

"World's Finest," "Supergirl's" anticipated crossover episode, arrives tonight, March 28 on CBS at 8 p.m.