Grey's Anatomy and Private Practice both return to ABC this coming Thursday, and when they do, the worlds of Shonda Rhimes will collide in a crossover once again.

In the 9 p.m. slot, Mark flies Addison to Seattle to help with a difficult procedure on his pregnant daughter, Sloan (Leven Rambin), on an all-new Grey's Anatomy.

Meanwhile, Owen questions Teddy’s motives re: Cristina, and Derek’s suspicions are raised when the Chief recruits Meredith to assist with a high profile operation.

Click to enlarge Grey's Anatomy pics from Thursday's episode, "Blink" ...

In the 10 p.m. slot, Mark follows Addison back to California to continue Sloane's treatment, while Dell and Naomi struggle to raise their children under the same roof, and Violet and Cooper disagree on how to treat a patient on Private Practice.

Follow the jump and click to enlarge Private Practice pics from "Another Second Chance" ...

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