"He comes over and he does drop his drawers. There's more McSteamy than usual that we see," said Walsh.
But they're not the only ones facing new drama in this episode.
"Mark and Addison have their own fish to fry," said actor Kevin McKidd.
"From the trailer we are led to believe that it gets steamy, but don't want to give away anything," said actress Kim Raver.
McKidd and Raver are relative new kids on the block at Seattle Grace. And they're not only enjoying their time with the "Grey's" cast and crew, they're enjoying the response they're getting from fans.
"I noticed it especially this year. I think when you get your feet under the table, people start to give you advice, relationship advice," said McKidd.
"The fans of this show, they know everything," said Raver. "I listen to what they say. They know more than I do."
Thursday night kicks off with an ABC News special covering the devastation in Haiti. The special cross over episodes of "Grey's Anatomy" and "Private Practice" begins at 9 p.m.