A jewelry shop owner undergoes open-heart surgery after being shot during a robbery.

A Woman is attacked by mountain lion. A difficult lady has abdominal problems.

Dr. Keller thinks a boy struck by a baseball bat has a concussion, but a CT scan reveals massive brain bleeding, and he suffers kidney failure.

An 11-year-old girl has streptococcal pneumonia, which has a high fatality rate.

A 7-year-old boy undergoes surgery to reattach his left arm after it was severed in a truck accident.

The force of a tornado drove a fence picket through Julie's neck.

A teenager rushes to the ER after a football game.

A skier hits a tree at 50 mph.

A stack of drywall collapses on a young boy.

A six-year-old girl is Rushed to the ER with intermittent Seizures.

A crazed gunman storms a large metropolitan hospital and opens fire in the ER.

A car accident ejects a young boy from a vehicle.

A team of doctors tries to save a patrol officer's life.

A rattlesnake bites the 2-year-old son of a snakebite expert.

A 4lb steel hook impales the skull of construction worker.

A ruptured brain aneurysm threatens to kill the ER's medical director.

A mugging victim arrives with two bullet wounds to the brain.

Follow the case of a boy with an oxygen deficiency and bizarre brown blood.