ER (OV)

In the emergency room of the urban Chicago teaching facility County General Hospital, a Level One Trauma Center, the difference between life, death, pressure, joy and guilt are overwhelming.

Moretti continues to institute new measures that cause many of the emergency room doctors to despise him.

When a teenage wrestler comes into the emergency room with severe vomiting, Pratt quickly tries to solve the problem, but he finds out that the cause is much more serious.

County General Hospital is turned into a beauty parlor for a day when a gracious former patient provides free beauty treatments.

Moretti (recurring guest star STANLEY TUCCI) decides that Gates has done an impressive job in the intensive care unit and is now ready to return to the emergency room.

When Moretti brings in a new attending physician, Skye Wexler, to help with the workload, Morris and Pratt find the time to cram for their medical board examinations.

In an effort to be more environmentally conscious, Morris buys an energy-efficient smart car. Meanwhile, Abby and Pratt try to treat a fussy baby but disagree on the diagnosis.

Gates and Julia nurture their newfound romance but are soon interrupted by a troubled phone call from Gates' ward, Sarah.

When Kovac's brother visits Abby, feels crowded in her own home. Meanwhile, Gates starts to experience the pressure of fatherhood after Sarah decides to have a sleepover with her friends.

In this special 300th episode, Kovac, Abby and baby Joe quickly make plans to go to Croatia after Kovac's father unexpectedly passes away, yet something still seems off with Abby.

When a young woman comes in with a badly hurt ankle, Sam is shocked to learn how much they have in common. Jeanie Boulet rushes into the ER after her son takes a fall during gym class.

Abby checks rehab and makes her way back to the ER. When multiple victims of a fire come into the ER, Abby thinks that one of the little girls is suffering from a degenerative eye disorder.

Pratt gets cold feet when Bettina tries to take their relationship to the next level. Neela joins the Ortho's hockey team and is shocked to see who their opponents are in the first game.

Pratt is off to a bad start with a new doctor, and Abby considers telling Kovac (former series star GORAN VISNJIC) the truth about her affair. Sam learns Gates and Julia broke up.

Neela makes a quick decision about a patient with a torn aorta (guest star AIDA TURTURRO - "The Sopranos"). Gates sends Sam flowers.

Neela is upset after she finds out the aorta surgery on Sheryl Hawkins (AIDA TURTURRO) has caused an infection. Kovac (GORAN VISNJIC) struggles to forgive Abby.

Pratt fights for his relationship with Betina (recurring guest star GINA RAVERA). Neela finds out about a patient's criminal status when one of them pulls a gun (JOSH STEWART).

Morris goes in for a psychological debriefing after his traumatic run-in. Neela is frustrated Sheryl Hawkins (AIDA TURTURRO) needs a fourth surgery. Abby is offered a new job.

In an explosive season finale, a mysterious patient (guest star STEVE BUSCEMI - "Fargo," "The Big Lebowski," "The Sopranos"), with very mysterious visitors, comes into the ER.