While rescuing an injured firefighter, Rox is hit by a drunk driver and rushed to Angels Memorial. Willis begins to realize his feelings for Rox and goes to great lengths to help her. Also, Leanne is excited to tell Ariel good news about her adoption.

The episode was rated 7.97 from 541 votes.

A code black at Angels Memorial takes a turn for the worse when a city- wide blackout leaves the hospital without power or back-up generators. As Campbell and Leanne divert high-risk patients to a nearby care center, Elliot and Heather are trapped in an elevator with a woman in labor, and Willis and Dr. Nolan try to help a 92-year-old woman who thinks it’s 1942.

The episode was rated 7.99 from 1074 votes.

Willis, Leanne and Jesse risk their lives to operate on an injured officer who has an explosive bullet lodged in her leg. Meanwhile, Mario, Noah and Guthrie treat a magician who comes to the hospital with breathing difficulties.

The episode was rated 8.00 from 1048 votes.

Willis must help a promising soccer player make a life-altering decision after he's seriously injured, and another patient's hesitation to share that she's transgender makes it difficult for the doctors to diagnose her severe abdominal pain.

The episode was rated 8.01 from 1079 votes.

Leanne, Neal, Christa, Angus, Mario, Malaya, and Heather are sent to the scene of a multi-car collision on a canyon road above Los Angeles. Leanne clashes with the physician in charge, making a decision he questions. Christa treats an injured family whose car is in a ravine. Angus, Heather, and Mario help a man stuck in cement. Mario and Heather find their lives in danger when a patient's husband holds them at gunpoint to save his wife. Meanwhile, Jesse recovers from his heart attack.

The episode was rated 8.02 from 730 votes.

The ER adjusts to the new department head who questions Rorish's decisions. An ambulance arrives with its paramedics knocked out by their patient, who attacks Jesse. Later, Jesse has a heart attack. As the doctors try to save him, other patients include a man hit by a train, the daughter of a controlling Beverly Hills mother, and the wife of a veteran who is struggling with addiction. Meanwhile, Mario leaves the hospital to find the train victim's son with intellectual disabilities, against Hudson's orders.

The episode was rated 8.03 from 734 votes.

On Halloween night, Willis, Noa and Elliott rush to the scene of a fire at a haunted theater, where Dr. Nolan and her boyfriend’s son are trapped,

The episode was rated 8.04 from 1089 votes.

Willis continues to tend to Rox’s medical needs in San Diego and Leanne and Max’s father go searching for Ariel. Also, when Noa reveals to Mario she wants to take a job offer in Philadelphia, and Campbell offers Mario the attending position at Angels, they realize their career choices will mean ending their relationship.

The episode was rated 8.06 from 501 votes.

Malaya must inform a college student who regains consciousness at Angels Memorial that she's the victim of a rape. Meanwhile, Willis and Campbell butt heads over a terminally ill woman who wants to end her life on her own terms; and a comedian is treated after he collapses on stage during a performance.

The episode was rated 8.08 from 1062 votes.

The ER is quarantined when a viral outbreak jeopardizes the lives of the doctors and patients at Angels Memorial. Also, Ariel, the young girl Leanne bonded with a year ago when she lost her father, returns to Angels.

The episode was rated 8.13 from 1114 votes.

The doctors are questioned following a violent incident inside the hospital that leaves two doctors gravely injured. Neal and Christa make their relationship to the next level after officially disclosing their romantic relationship to HR.

The episode was rated 8.13 from 759 votes.

Guthrie becomes the hospital's new chaplain and considers undergoing a risky surgery to treat his Parkinson's. Meanwhile, the doctors treat patients involved in an apartment fire.

The episode was rated 8.13 from 1059 votes.

When the lead actor of the musical “The Lion King” tour arrives at Angels Memorial with a throat infection, Leanne gives him a diagnosis that puts both his career and life in jeopardy. Also, the doctors and the cast of “The Lion King” help a 17-year-old boy deal with the difficult decision of taking his father off life support,

The episode was rated 8.13 from 724 votes.

The doctors work with the Center for Disease Control and Prevention to find an antidote to the deadly viral outbreak at Angels Memorial. Also, Leanne makes a life-changing decision, and Jesse welcomes a new batch of residents.

The episode was rated 8.25 from 1078 votes.

Angels Memorial descends into chaos when a plane crashes into the 8th floor. Also, Noa has a car accident and it is up to Mario to save her life. Also, Willis admits to Rox that he needs her in his life and the doctors gather in court to support Leanne for her custody hearing.

The episode was rated 8.31 from 493 votes.