Season 8 - Episode Guide

A young girl is brought to the hospital with stabbing pains in her scalp. A wife and mother is struck down by a severe string of mysterious symptoms that threaten to tear her family apart. A deadly invader turns a relaxing vacation into a nightmare.

A man falls comatose. A college student's sore throat turns deadly. A woman's bizarre symptoms confound experts.

A man experiences bizarre swelling around his eye. A 12-year-old girl falls mysteriously ill. A young woman is struck by a bizarre set of symptoms that leaves her on the verge of madness, and neither her family nor her doctors can understand why.

An infant falls mysteriously ill. A biology professor becomes an unexpected host. A family man is brought to the brink.

Doctors discover an invader in a young man's brain; a new mother is in critical condition; a young boy's illness defies antibiotics.

A boy is struck down with a strange condition. A woman has bizarre symptoms that push her to the brink of madness. A toddler falls into a trance-like state.

A teenager develops mysterious blotchy sores. A tough athlete is struck down by a rare disease. A woman battles strange bouts of vomiting.

A man starts coughing up blood. A newlywed husband is struck down by a rare disease. A young father experiences crippling abdominal pain.

An infant is suddenly paralyzed. A young father grapples with a monster that threatens to blind him. A woman's excruciating pain confounds experts.

A young woman is struck down by a dangerous parasite. An infant becomes mysteriously ill. A midwestern man is brought to the brink by a deadly fungus.

A man bangs his head and is left fighting a rare medical mystery; a wound in a boy's knee harbors an uninvited guest; a man unwittingly feeds his own intended killer.

A man develops a strange growth on his wrist. A nurse sees twig-like pieces in her urine. A pregnant woman falls dangerously ill with flu-like symptoms.

Three unsuspecting victims see the holidays turn from a time of joy and merriment to fear and agonizing pain as they battle against mystery attackers trying to destroy them from the inside out.