Cristina asks Owen, "Do you love Teddy or do you love me?" and when he can't answer, she breaks up with him. Cristina's mind is still on Owen when Clark asks her where he can find Dr. Shepherd. She gives him directions to Derek's office. We hold our breath until the elevator opens, and then he tells her, "Have a nice day."
April finds Reed's body. She's hysterical as she runs into Derek's office covered in blood and tells him that someone shot Reed. Derek orders a lockdown of the entire hospital and leaves April in his office while he goes to warn Teddy and Owen, who are in surgery. He tells Jackson that there's a shooter in the hospital, but not to say a word to anyone else until the patient is stable.
Callie is barely speaking to Arizona after their breakup, but now they're sealed together in the pediatrics ward.