If there’s one thing Grey’s Anatomy is known for aside from being one of the best dramas on TV it’s serving up a jaw-dropping season finale. So what’s in store for Grey Sloan Memorial during the Season 9 finale?

Wetpaint Entertainment got the scoop from series star Chandra Wilson, who promised lots of drama when the hospital goes into “crisis mode” after a blackout. As if that wasn’t enough, Chandra says there’s also a lot of “personal stuff” going on behind closed doors.

For more scoop on the Season 9 finale, plus what you can expect from Season 9, Episode 21 (“Sleeping Monster”), read our entire interview with the heart of the hospital below.

Wetpaint Entertainment: Bailey is going through a tough time right now. She might be responsible for this deadly post-op infection. What’s going to happen to Bailey?

Chandra Wilson: So when we left her, she had to have a seat, and that’s something she doesn’t do very well. She gets grounded. The CDC has to come in and do what they need to do, so we can get to the bottom of where this infection came from to make sure we can prevent other cases. We need to make sure those other patients are OK. Under normal circumstances, that would be fine. If this was happening to any of Bailey’s colleagues, she’d tell them to have a seat and let the people do what they need to do, but her own ego is not allowing her to hear that. Therefore, she takes everything incredibly personally.

Well, if you look at the members of the Board, there’s Meredith, Cristina and Derek, who are obviously going to fight for her, right?

Yes, they do, but a lot of that fight happens away from her. She has no idea that’s even happening. The only thing she sees is that she’s been grounded, and not only does everybody support that, but she also doesn’t see where anybody is rallying for her. And that’s hard!

In one of the sneak peeks, we see Meredith try to help her.

The interesting thing about that scene is that it’s a private moment between the two of them, but when it’s out in the open, when it’s in front of the hospital — I believe in that scene Avery sees them talking — then Meredith gets called to the carpet for that because she needs to be a board member right now. She can’t be a friend. And that’s what Bailey is having problems with. The positions are taking precedence over the relationships.

It’s been incredible to see the evolution of Bailey as a character, from her early days as the Nazi to someone who is now considered to be the heart of the hospital. Has that been incredible for you as an actor?

The thing that I always have to remember — the common thread with that — is that Bailey does have an incredible ego. Whether she’s barking orders or she’s owning her position as the heart of the hospital, it’s all something that she personally, and the thing that never gets called into question, is her competence as a surgeon. And that’s why this whole CDC investigation is really difficult for her because she knows without a doubt — and everyone else should know — that she didn’t do anything wrong. Something happened, and for whatever reason, she’s made to feel that she did something wrong. That’s really unforgivable for her.

We know that in future episodes she starts to shut the other doctors out.

It’s payback! It’s absolute payback. She feels as though she should have been treated in a certain way by the people who were supposed to be her friends as opposed to being treated like an employee. She really just doesn’t have time for that.

Do you miss that sassy side of her?

She gets back to it often enough! In one of the recent episodes, she was spending all of her time yelling at Leah for leaving crumbs on her laptop! So all of those shades of her are still there. You just don’t see her walking around with five interns behind her anymore. That part of her teaching philosophy and that part of her personality is still there, and I certainly try and find opportunities to show it to viewers when I can.

You’ve directed a few episodes of Grey’s in the past. Are you looking forward to doing more of that if there’s a Season 10?

I’ve been directing at Grey’s for the last four seasons. I usually do one in the fall and one in the spring, and I’ve kept my realm of possibilities open for more opportunities. Grey’s really consumes all of us, from July to the beginning of May, every year. It’s amazing, and I knock on wood for it every time, and so the thing for me as an artist and director is, do I step away from that at any point so I can go off and do other projects? Or do I wait until Grey’s is done to then go off and do other stuff? Grey’s takes the priority for me as an actor, but in the meantime, this amazing other gift has been given to me, as a director, to be able to take with me, going forward. I just keep learning.

We just found out the title of the Season 9 finale is “Perfect Storm.” What can you tell us about the episode?

You can take “Perfect Storm” however you want to take it! There’s a lot of innuendo in there. The hospital does have to go into crisis mode in order to make itself available in case there are emergencies because of the storm. But we still have a lot of personal stuff going on at the same time. And you know it’s a Grey’s season finale, so it’s not going to be simple! It’s not simple at all.

Uh-oh. Are you excited or nervous for the Season 9 finale? Sound off in the comments below!

Catch the next new episode of Grey’s Anatomy on Thursday, April 25, 2013, at 9 p.m. ET/PT on ABC.