A woman believes her neighbors want to kill her; a man is near death after an arrow pierces his chest; two women with swollen abdomens refuse to explain the cause of their pain.

An ER doctor's friend arrives at the hospital combative and out of control; a cyclist's throat is torn open when a driver opens a car door in her path; a nursing student is found passed out on the hospital floor.

A man is impaled in his abdomen by a stiletto heel; a seemingly healthy outdoorsman has a series of seizures that baffle his doctors; two patients make their doctor suspicious when they both complain about identical headaches that started during sex.

A young pregnant woman in labor begs the ER doctor to keep her pregnancy a secret from her father; twins share confusing symptoms; a man with no pulse or blood pressure is still alive and breathing.

A young boy at a sleepover party mysteriously loses control over his arms and legs; a woman is shot in the leg at her own bachelorette party; bubbles in a woman's arteries are causing a stroke.

A patient suddenly starts seizing; an ER physician is at a restaurant when she is thrown into an emergency situation to save a child; a pregnant woman's heart is racing.

A young girl is mysteriously paralyzed from the waist down; a young man complains of a splitting headache; a bride-to-be has appendicitis on her wedding day.

Doctors use a robot to treat a seizing 7-year-old boy; a chef's tongue is swelling; a woman who crashed her car insists her injured dog be treated first.

A circus sword-swallower suffers from a persistent case of hiccups; a mother and daughter mysteriously collapse in the ER; a woman loses control of her legs at her daughter's graduation.