A drug bust-turned-shootout tests the bravery of the doctors of Angels Memorial as they race to save a girl caught in the crossfire. Also, Willis shifts his focus to field medicine, choosing to work primarily on an ambulance with his new partner, paramedic Rox. And Leanne begins her journey to adopt Ariel.

Jesse is in denial when his brother arrives at Angels Memorial in bad shape after being pinned down in a warehouse collapse, and further tests reveal he has advanced congestive heart failure. Also, Willis opens up to Rox about his brother who was killed in Afghanistan.