Maggie and Meredith disagree with Derek about the best way to approach a patient's case, which leads to a bigger argument between the couple. Meanwhile, Callie feels responsible when one of her veterans is pushed too far and one doctor's routine procedure results in a devastating diagnosis.

April stays optimistic as Arizona begins testing on her baby; Dr. Herman plans out a crash course in fetal surgery; and Owen and Callie encourage each other to get back into the dating scene. Meanwhile, Meredith, Maggie and Bailey use the 3D printer to gain a better understanding of their patient's tumor.