[s6e5] Invasion -

: Fans often remember this episode for the "dark and twisty" bonding between Cristina Yang and Alex Karev, both of whom seek solace in Meredith's room as they deal with the fallout of the merger.

: The episode was written by Mark Wilding and directed by Tony Phelan . [S6E5] Invasion

: This episode served as the first half of a crossover event with the spin-off Private Practice . The storyline of the patient Izzie endangered, Sarah Freemont, concludes in the Private Practice episode "Right Here, Right Now". : Fans often remember this episode for the