Plot Synopsis

Biologist Dan Riskin investigates the cases of people who battled parasitic infections, and he gets some help from the doctors and experts who witnessed each case. Each 60-minute episode features three different stories, including these cases in Season 3: toddler Isabella, who stops eating and suffers bizarre salt cravings, followed by a significant elevation of eosinophils, white blood cells that fight particular allergens and infections; Californian Tom, whose doctors discover that his colon is perforated, believing that he has diverticulitis, which occurs when small pouches in the colon become clogged and infected: couple Tom and Lucina, who fall ill after having a drink on vacation in New York City and become infected with an organism that kills 50% of those infected; model Kathryn, who suffers from extreme pain after childbirth which doctors first believe is caused by an infection in the breast tissue -- but are later surprised to find the real culprit; Boy Scout Matthew, whose flesh is decaying while doctors initially diagnose his condition as sinusitis, an infection that fills the nasal cavities with mucus; 19-year-old Sarah, who is suffering from something much worse than walking pneumonia -- could it be blastomycosis, a fungus that infests the deepest cavities of her lungs?; and many more tragic and scary stories of medical maladies.

MONSTERS INSIDE ME returned for its fourth season on Monday, September 30, 2013 at 9pm ET/PT. In the season opener, Dan investigated the medical cases of a seven-year-old girl who suffered from painful rashes and mysterious seizures, ending up in a coma, as well as that of a yoga-loving college graduate, whose health spirals out of control because of a flesh-eating monster. Other cases in Season 4 include: a teenage ballerina, who suffered from painful migraines and muscle failures; a young missionary, whose skin crawled when he uncovered an unholy revelation; and many more people who suffer from outrageous medical maladies.

MONSTERS INSIDE ME returned for its fifth season on Thursday, October 9, 2014 at 10pm ET/PT on Animal Planet. In the season premiere, "My Daughter's Going Crazy," three women living in vastly different locales have one thing in common: they've become unwitting hosts to baffling and deadly terrors. Also, a teenage girl thinks she might be losing her mind, but she soon realizes that she has a life threatening inflammation of the brain. The rest of Season 5 highlights stories about people who are victims to teratoma, West Nile virus, rat lungworms, acanthamoeba keratitis and much, much worse. Plus, MONSTERS INSIDE ME also reveals the rare, but possible, consequences of negligibly washed produce and the little-known dangers of fungus.

Season 6 of MONSTERS INSIDE ME premiered on Thursday, October 29, 2015 from 9-11pm ET/PT, as Animal Planet debuted back-to-back new episodes immediately following an all-day marathon (9am-9pm) of encore episodes. Host/biologist Dan Riskin returned for ten new episodes, providing a scientific perspective of the cringe-worthy creatures, which made hidden crevices of our bodies their homes. In the season opener (9pm), "There's Something Living in My Knee?!," the worlds of three families are turned on their heads. A mysterious outbreak leads to a four-year-old boy drowning in his own mucus. A wound in a seven year old's knee has a vile cause. And bizarre dreams precipitate a college student's hospitalization. Then, in the night's second new episode (10pm), "Help! My Son is a Leper," the lives of three families are twisted in knots. A mysterious infection brings a tough ultra-marathoner to his knees. A teen contracts one of the planet's most feared diseases. And a woman's brain is practically set on fire. Season 6 continues with back-to-back new episodes on Thursday, November 5 from 9-11pm ET/PT and then single new episode each Thursday at 10pm starting November 12.

Season 7 of MONSTERS INSIDE ME premiered on Thursday, October 6, 2016 at 10pm ET/PT on Animal Planet. Biologist Dr. Dan Riskin is back as host, as the new season kicks off with a special episode looking back at three of the craziest cases that have stumped viewers. The shocking stories continue with 15 new cases in five all-new episodes that could leave one second guessing their every move. From a toxic trinket and a disease transmitted from animals to an alarming eye infection and bacteria found in all freshwater environments, these microscopic monsters are closer than you think and ready to cause havoc to any body they can find.

On Sunday, October 15, 2017 from 9-11pm ET/PT, Animal Planet premiered the eighth season of MONSTERS INSIDE ME, debuting back-to-back new episodes. Season 8 reveals some never before seen invaders causing the most gruesome cases yet with victims of deadly attackers such as parasites, viruses, bacteria, foreign objects and fungi. This season, MONSTERS INSIDE ME investigates mystifying medical cases including: a young boy with a mysterious infection who becomes plagued with the sensation that something is alive inside his head, and a woman with a mysterious Teratoma filled with teeth and hair. Watch as doctors race the clock to diagnose and treat these debilitating and sometimes life-threatening illnesses before it's too late. Plus, the night of the season opener, Animal Planet debuted these episodes: "Help! I'm Being Eaten Alive" (9pm): A young girl is brought to the hospital with stabbing pains in her scalp infested with flesh-eating parasites. A wife and mother are struck down by a sever string of mysterious symptoms that threaten to tear her family apart. A deadly invader turns a relaxing vacation into a nightmare. "My Brain Is Under Attack" (10pm): A man falls comatose, a college student's sore throat turns deadly, and a woman's bizarre symptoms confound experts.
----------------------------------------------------------------------------------------------------------------------------------------------------------------
On Thursday, December 21, 2017 at 10pm ET/PT, Animal Planet premiered "Hell-iday Horrors," a one-hour MONSTERS INSIDE ME holiday special. For three unsuspecting victims 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, all during "the most wonderful time of the year."