As we're sure you're aware by now, Seattle Grace and Mercy West are merging, and that means a new crop of doctors aiming to put our favorite Grey’s Anatomy characters out of work.

October 15 is the day the staffs merge, fittingly in a tense episode titled "Invasion." Word is that specifically, Izzie Stevens and Lexie Grey find their heads are on the chopping block.

“We’re not the most welcome faces at Seattle Grace,” says newcomer Robert Baker.

But off set, the new blood has welcomed with open arms, especially by Justin Chambers (Alex Karev), who recently took them all out to lunch!

Here's some scoop on what we can expect from the newcomers ...

Izzie and a pair of Seattle Grace's new residents.

• Dr. Jackson Avery (Jesse Williams) “He’s a very confident, competitive, fearless leader and a bit of a cocky, hotshot surgeon,” says Jesse. “He’s cracking jokes left and right and going in there and taking no prisoners. So far, I’ve had a spat with Cristina and shared scenes with Owen, Lexie and Derek.”

• Dr. Reed Adamson (Nora Zehetner) “She’s very feisty and comes on a bit strong at first,” says Nora, a longtime friend of Chyler Leigh (Lexie). “But she’s a good doctor who cares a lot about the patients, especially with the merger getting in the way of that. Everyone is in competition and worried about getting fired, so there’s a lot of fighting with Izzie, Alex and Cristina for the best surgeries.” As for romance with Alex, Nora says only “Perhaps.”

• Dr. Charles Percy (Robert Baker) “He’s a general surgeon who has a problem keeping his mouth shut,” says Robert, who has shot scenes with Bailey, Alex and Derek. “In my first episode, some complications arise between Charles and Izzie, causing head-butting. Then some things happen that the fans will definitely want to see.” Could these characters share more than scalpels? “Izzie’s a married woman, but never say never.”

• Dr. April Kepner (Sarah Drew) “April’s eager, a little insecure, passive-aggressive and tries to undermine Lexie,” says Sarah, who has “really enjoyed playing a bitch.” But April also has a sensitive side. “You’ll see her writing some surprising things in her journal.”

Are you excited for the new cast members? Comment and vote below ...

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