Comic-Con 2012 Posters

Seth Green is set to guest star on Grey's Anatomy in Season Four. The oddball comic actor does voices for Family Guy and has starred in flicks such as Can't Hardly Wait and the Austin Powers trilogy.

Lauren Stamile has been announced as the newest guest star of Grey's Anatomy. We're interested to hear what the writers have in mind for this cutie.

The former Dawson's Creek star is reportedly coming to Grey's Anatomy in Season 4. We are looking forward to seeing with Joshua Jackson has to offer.

Ron Melendez of "General Hospital" fame will be coming to Grey's Anatomy as a guest star in Season Four. We're looking forward to it already.

Diahann Carroll will return to Seattle Grace in Season Four, even with Preston Burke (her character's son) gone from the show. We're looking forward to seeing this amazing actress return once again.

A photo of Elisabeth Reaser, best known to Grey's Anatomy fans as Jane Doe (or later, Rebecca Pope). She's a good actress and is coming back for at least part of Season 4.

Tony Award winner Ben Vereen has been added to the cast of Grey's Anatomy in a guest starring role for Season 4. We're looking forward to seeing who he plays!

Edward Hermann, best known for seven years on "Gilmore Girls," will be guest starring on Grey's Anatomy in Season 4. We're looking forward to seeing who he plays!

He's a single guy again, ladies. Go after Jeffrey Dean Morgan while you can!

Will new guest star Chyler Leigh mean more friction between Derek and Meredith.

Co-starring on the forthcoming Grey's Anatomy spin-off with the lovely Kate Walsh.

He's hunky and narrating the newest Season 3 recap show.