We know that production is well under way on Season 4 of Arrested Development, with new episodes slated to debut on Netflix early next year featuring the entire original cast. Today, we have word that the show has brought on Mad Men star John Slattery to appear in a multiple episode arc.

It isn't immediately clear what character the actor will portray. Perhaps he will play an estranged Bluth relative? Or maybe a new neighbor? At any rate, executive producer Ron Howard did hint that new characters may be popping up throughout the 10-episode season, in a recent interview.

"(Series creator) Mitch (Hurwitz) isn't trying to recreate something. It's been away for a while, and part of the fun that Mitch has been mining and exploiting is, what's new to discover about these people? What's delightfully unchanged? He and the writing staff and the actors have a fantastic sense of that. They're pretty brazen, pretty bold and fearless. That's what made the show into something that fans really kept alive."

Don't be surprised to hear about more casting additions as production continues on these highly-anticipated episodes.