Rumors of an upcoming, joint ABC hour-long special for Grey's Anatomy and Private Practice are true: "Come Rain or Shine: From Grey's Anatomy to Private Practice" is scheduled for Wednesday, September 19 at 9 p.m.

The special offers an intimate look at Dr. Addison Montgomery from her arrival in Seattle to her turbulent life and quest to start a new one.

While there have been scant marketing efforts to promote the Grey's spin-off this summer, this special is clearly meant to prepare us for Private Practice.

Addison (Kate Walsh) has put her ex-husband Derek (Patrick Dempsey) and the rest of her life in Seattle behind her. She's ready for a new beginning!

Additionally, this special will feature a new Grey's Anatomy music video made out of the song "Breathe In Breathe Out" by Mat Kearney.

The special will also feature a first look from the new season of Grey's Anatomy and clips from the series premiere of Private Practice. Should be great to watch and get people involved. Check out this promo in the meantime!

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