The team investigates recent encounters with a monstrous apex predator in the wilderness of British Columbia; using never-before-seen clues from Ivan Sanderson's lost archive, they uncover new evidence that may finally distinguish fact from fiction.

The team makes a discovery while investigating sightings of a large bird of prey terrorizing Chestnut Ridge, Pennsylvania; Sanderson believes it to be the mysterious thunderbird, a razor-clawed predator documented in Native folklore.

The team investigates a stranger-than-fiction murder mystery involving the Wildman of Minnesota; known as the Ice Man, its body became a sideshow attraction that Sanderson examined himself before it mysteriously disappeared.

A mysterious apex predator is stalking orcas and boats off the coast of Kodiak, AK; sea monster sightings, first studied by Sanderson before his death, have spiked in that area recently.

When Ozarks locals report frightening encounters with a mysterious, dragon-like beast, the team conducts their most ambitious hunt yet.