During last night's Brothers & Sisters episode, ABC ramped up its promo for the Grey's Anatomy-Private Practice crossover event this Thursday with a 45-second advertisement.

While we've seen a lot of these snippets from the much anticipated 2010 debuts of both Shonda Rhimes series already, they've never been packaged quite this dramatically.

Or in the case of Mark and Alex, nakedly.

The promo for "Blink" and "Another Second Chance" leaves little doubt that more than one relationship may be in peril along with the life of Mark's pregnant daughter.

If you missed it, we posted a huge photo gallery for both episodes as well as five sneak previews this weekend. Check out the promo below and share your comments:

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