When an emergency occurs, the San Francisco City Hospital trauma team is the first on the scene no matter where the victims are. Flight medic Reuben "Rabbit" Palchuk, paramedics Cameron Boone and Nancy Carnahan, rookie pilot Marisa Benez, EMTs Tyler Briggs and Glenn Morris, and mentor Dr. Joe Saviano must fly into action when tragedy strikes close to home.

The team is sent to the scene of a major accident in which a car lost control and crashed through a street fair. Meanwhile, Nancy gets a new partner and Rabbit teaches Marisa a valuable lesson.

Boone's relationship problems are forced to be put on hold when aballoonman goes on a rampage inside an office complex. The shooting causes Rabbit and Nancy to have to work together for the first time in over a year. Meanwhile, Marisa realizes how similar she is to Rabbit.

Tyler and Boone respond to an accident in a Chinese restaurant and there they find that the explosion is more serious than they thought. Meanwhile, Nancy's medical expertise is put on test. Meanwhile, Rabbit has a weird reaction to a flight.

It's Halloween time in San Francisco and anything can happen. Tyler and Boone are on the scene when a Halloween party erupts in chaos. Meanwhile, Nancy and Glenn's shift takes an unusual turn. Elsewhere, a secret that can change a partnership is revealed.

The tables are turned as Nancy and Glenn find themselves on opposing sides of a trauma. Elsewhere, the on-scene priorities of Boone are questioned, and Rabbit has a surprising reaction while treating a patient.

Glenn risks everything to follow his heart's desire. Rabbit helps a patient cope with a tragic loss. And an old friend surprises Marisa.

The team responds to a chaotic accident involving a wedding at sea and a speedboat collision. Elsewhere, Nancy takes a break from her hectic schedule to bond with her family.

During Thanksgiving, a full commercial airliner is forced to make an emergency landing but it goes horribly wrong. Meanwhile, Nancy reluctantly spends the holiday with her family; and Boone and Tyler respond to a common Thanksgiving mishap.

When a bad batch of heroin is being dealt on the streets of San Francisco, Glenn questions Nancy's response to a "frequent flier." Meanwhile, Marisa sets out to track down a bizarre theft; Boone takes a new step that will affect his future; and a new romance blossoms.

Nancy must face one of her greatest phobias while treating a construction worker trapped underground after falling down a manhole. Meanwhile, Rabbit and Marisa are on the scene of a bank robbery to treat the injured. Elsewhere, Boone has a new position and his first decision may jeopardize the career of one of his own.

Glenn handles a procedure by the book and loses a patient, bringing the whole station under a "probie curse." Meanwhile, Rabbit's suspension leads him to mandatory therapy sessions to regain his wings as his relationship with Nancy intensifies. Elsewhere, Marisa deals with a new partner, while Boone and Tyler have a patient jump out of the rig.

Rabbit has a breakthrough in therapy that reveals a traumatic event from his past. Meanwhile, Nancy and Dianas difference of opinion puts a patients life at risk. Elsewhere, Tyler and Boone consider their futures, as Glenn reaches a career milestone.

Glenn and Nancy are caught in the crossfire when San Francisco is taken hostage by a sniper; Boone tries to get used to Tyler's new paramedic status.

Nancy ignores protocol while treating a high-school cheerleader; Rabbit and Marisa are quarantined after being exposed to a patient with meningitis; a misunderstanding tests Boone's partnership with Tyler.

A patient who regularly abuses the system calls again for help. Nancy has problems with her father's new job and Boone disagrees with Tyler on how to treat a patient at a mosque. Also, a dream unsettles Marisa at work.

In the process of gathering stories for his book, Glenn finds himself discussing unusual calls with his work mates and ends up hearing much more than he imagined. Elsewhere, Tyler's dad comes to town for a visit.

A problem with dispatch creates chaos when medics are sent scrambling to the wrong locations. Marisa reconnects with her army buddy Casey but their visit takes a dark turn. Boone plans a surprise party for Tyler's birthday. Elsewhere, Nancy, who has a lot on her plate as she deals with a terminal cancer patient, ponders the next step with Rabbit in their relationship.