Life here is measured in seconds, and these heroic doctors and nurses operate with speed and skill within an overwhelmed system to heal people who are often there for one of two reasons: to die or to receive a lifesaving miracle.
At the heart of the ER is Dr Leanne Rorish (Marcia Gay Harden), a stop-at-nothing residency director whose job is to save lives in an often-impossible environment. Her team includes Luis Guzman as senior nurse Jesse 'Momma' Salandar and Rob Lowe as Dr Ethan Willis, a U.S. Army colonel attached to the prestigious Combat Casualty Care research program.
In the third series they are joined by Moon Bloodgood as Rox Valenzuela, a paramedic who is Dr Willis's new 'ride-along' partner. With the hospital surviving a deadly virus at the end of series two, and Leanne set to adopt Ariel in this series, the private and professional once again mix to dramatic and emotional effect.
In the opening episode of the new season, 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.
Meanwhile, Ethan Willis shifts his focus to field medicine, choosing to work primarily on an ambulance with his new partner, paramedic Rox Valenzuela and Leanne begins her journey to adopt young orphan Ariel (Emily Alyn Lind). Other new arrivals at the ER are first year resident Diego (Tyler Perez) and Pepper (Chaley Rose), a new resident who may not be ready for the frenetic pace at Angels.