These are the chilling cases of law enforcement officers facing monsters. From the terrifying �Beast of LBL� to a Bigfoot encounters in Oklahoma and Washington State, first responders confront creatures that defy logic and warp reality.

From a demonic entity in Bagdad Iraq, a haunted house in England, a UFO over the skies of Kentucky and a Djinn on the Balad Air Base in Iraq, marines, soldiers and airmen come face to face with forces no training could ever prepare them for.

These are the chilling encounters of people who trespassed into the domain of the unexplained... and paid the price. From Bigfoot in Washington State and Maryland, a Skunk Ape in Florida, to a spirit in Washington state and a dogman in Kansas.

These are the chilling accounts of people who claim they were hunted by mysterious cryptids. From a Dogman in Ohio, a Skunk Ape in Florida and a mysterious Wendigo in Wisconsin, these cryptid predators stalk their human prey.

MonsterQuest goes to the Azores in order to look for an albino sperm whale and investigate the theory that such an animal would be hostile.

Inventor Robert Rines, who believes he saw the Loch Ness Monster surface in 1972, searches for evidence to prove his theory that the creature has died.

Mysterious cattle killings plague North American plains for decades. Cases involve mutilation, blood drainage, missing organs, and high radiation levels. MonsterQuest investigates with samples for scientific analysis, seeking answers to the enigma.

A swamp beast immortalised in the film "The Legend of Boggy Creek" is said to stalk the residents of a small town in Arkansas.

What is the truth about the Jersey Devil, which has been described as a winged half-bird, half-horse creature with hooves, a reptilian tail and a scream that echoes through New Jersey's Pine Barrens?

An urban legend comes true during the 1930s when New York City workers find swarms of alligators living beneath the busy streets of the metropolis.

The team hunt for a legendary creature that preys on elk, and perhaps even people, in the Colorado Rockies.

Investigating sightings of a 60-foot shark that might be a giant new species or a prehistoric survivor in the waters off Mexico's Baja Peninsula.

The team investigates increasing reports of Bigfoot encounters from across the United States.

Investigating the history of eyewitness accounts of a 50-foot monster known as Ogopogo sighted in Lake Okanagan in British Columbia, Canada.

An expedition investigates controversial evidence that might confirm a history of sea monster sightings off the coast of Florida.

In the Pacific Northwest, an investigative team searches for evidence of Sasquatch on Vancouver Island, where Native Americans once told tales of an ape-like beast that would steal children away.

Expeditions search for the Goliath grouper off the coast of Florida and a monstrous fish with frightening teeth beneath the icy surface of lakes in Minnesota.

The Tasmanian tiger was thought to have become extinct 80 years ago, but eyewitness reports and scientific research might indicate that the creature is on the verge of making a comeback.

The team go on a dangerous search in the Sea of Japan and along Australia's Great Barrier Reef to investigate reports of a jellyfish invasion that threatens to turn oceans into deadly places to swim.

Investigating reports from Papua New Guinea of a terrifying monster with a 20-foot wingspan known as the "Demon Flyer" that some people think might be a prehistoric pterosaur.

Investigating reports from India of encounters with a ferocious half-man, half-ape creature dubbed the monkey man.

Across the world, people are reporting increasingly frequent encounters with frighteningly large crocodiles.

Searching the jungles of Central Africa for an elusive monster said to resemble an enormous, long-necked and four-legged saurpod dinosaur believed to have gone extinct 65 million years ago.

Investigators try to compile and analyze evidence to prove that the elusive monster known as sasquatch exists, including videos, tracks, prints and maps of sightings.

A team searches for feral dogs to uncover where they live and determine how dangerous they are in the wake of reports of predatory packs of canines attacking people.

MonsterQuest goes to Mexico to investigate the phenomena of Unidentified Flying Humanoids.

MonsterQuest looks into reports of chimpanzees on the loose in the United States.

MonsterQuest looks into claims that large cats are on the prowl in the forests of the United States.

MonsterQuest uses the latest high-tech equipment to take a scientific look at legendary creatures around the world, creatures eyewitnesses claim to see to this day.

Great white sharks are the ocean's deadliest killers and as they swim closer to our beaches, attacks against humans are on the rise. MonsterQuest leads an expedition to examine why these monsters are becoming more aggressive predators.

A search in Eastern Kentucky for an elusive creature that is said to make terrifying, wild screams. Investigators look at photographic evidence, and explore the deep woods in an attempt to find the source of these mysterious sounds.

A deadly, slithering menace is taking over Florida and may be heading north. Discover whether pythons could hybridize and adapt, enabling them to threaten every state in the US.

MonsterQuest looks into reports of Africanized Bees in the southern United States and examines the theory that the bees are adapting to colder weather in spreading further north.

MonsterQuest goes to West Virginia to look into the Mothman examining both the original 1967 case and more recent sightings.

MonsterQuest investigates whether a breeding population of Amazonian piranha can survive in the waters of North America.

In 1967, a giant winged monster reportedly terrorised the skies over a small town in West Virginia. MonsterQuest uses nighttime surveillance, perception tests and forensic sketching to determine if the beast is myth or frightening reality.

For centuries the Amazon has been home to the most ferocious fresh-water monsters known to man - piranhas. With these creatures appearing in US waters, the team investigates whether the carnivorous beasts could breed and devastate local waters.

Ancient petroglyphs in the Sierra Nevada mountains depict footprints left by frightening packs of hairy man-like beasts. Now, MonsterQuest heads to the heart of California where witnesses are encountering aggressively territorial packs of Sasquatch.