Now that Mercy West's doctors have invaded and turned Grey's Anatomy upside down, they're staking their territory, which may include some new, intriguing relationships.

Dr. Charles Denman (Robert Baker) is at the center of the drama.

The new guest star opened up to TV Guide this week about what it's like to become the new worst enemy of the fans of one of TV's most popular shows in just one week.

He also discusses which Seattle Gracers will cross over to the dark side, how Thursday's episode unfolds and what Izzie (Katherine Heigl) will pursue when she returns ...

Q: Everyone hates the Mercy Westers. How does that feel?

Robert Baker: I've never been so hated in my life, but I think that it's the way [fans] should feel. We came on to the show and started wreaking havoc. I'm not like Charles in my everyday life. If I step on an ant, I go into mourning over it.

I don't want to ruffle any feathers in real life, so to go up there and do it is actually a blast. The show needs a bad guy. You can't have good drama without [one].

Q: Do any of them have any redeemable qualities? Will fans grow to like them?

Robert Baker: Yeah, people are going to start seeing that when it comes to doing our jobs, we definitely come through for them. I think it's going to take a while for people to be won over by any one of the Mercy Westers in particular.

It's going to be difficult in future episodes for them.

Q: Charles pretty much got Izzie fired. Will everyone in the hospital be upset with him?

Robert Baker: Certain people, definitely. I'm sure you can guess which people will be angrier than others about Izzie departing - not everyone though. They're not happy because she's gone; they're just not mad at [Charles] for what happened to her.

Q: Are Alex (Justin Chambers) and Charles going to come to blows?

Robert Baker: It's funny, this Thursday, Alex and I do have some stuff together. You will see his dislike for me. We don't quite come to blows because that wouldn't be a very fair fight, first of all. Clearly I'm the biggest person to ever set foot on that set.

Basically, it's a little more passive-aggressive what goes on between he and I. He has me under his thumb a little bit and takes advantage of it.

Q: Charles has admitted he's in love with Reed (Nora Zehetner). What's coming up between them?

Robert Baker: It hasn't really come up that much since, but it seems like something might - since Reed and Karev kind of mix it up, and the two of them have that competitive attraction sort of thing, I don't know if there's going to be some sort of weird triangle thing or what.

Q: Are there any other love interests in the hospital? There is a new gaggle of doctors; I'm sure people are giving them a second look.

Robert Baker: I know that Cristina [Sandra Oh] and Jackson [Jesse Williams] are pitted in an adversarial relationship that always, on Grey's, seems like it leads elsewhere. The fighting leads to something else. [Laughs] I think maybe them. I'm the odd man out; nobody likes me. The bad guy is always the lonely guy.

Q: The Mercy Westers seem to have the upper hand. We've seen them succeed a lot; will we see them fail?

Robert Baker: You're definitely going to see us fail and pretty darn hard. There is comeuppance, so people who are waiting for Mercy Westers to feel the ax, they're going to be happy.

Q: What can you tell us about Thursday's big episode?

Robert Baker: There's been a massive apartment-building fire. It's just total chaos. It's a he-said-she-said. There's too many doctors and too much commotion. It's all centered around one patient who we lose. It's trying to find out who was actually responsible for the death of this young lady. I can neither confirm nor deny the hospital of origin of the killing party.

Q: What's coming up when Ellen Pompeo and Katherine Heigl return?

Robert Baker: Now that Ellen is back around and Katie is coming back, it's going to be more about reconciling these worlds. I can't say when or how she comes back, but I can definitely say that Izzie is going to give as good as she got when she gets back around to me. People can definitely to look forward to seeing her score some points on [Charles] in the near future.

Steve Marsi is the Managing Editor of TV Fanatic. Follow him on Google+ or email him here.