Episode Thirteen takes them to every ghost hunter's holy grail: the Paranormal Research Foundation. This brooding, derelict mansion holds secrets and clues about bizarre experiments that took place there in the 1970s. It's also famously haunted, and the team hopes their scientific techniques and high tech gear will prove it. But as the house begins to reveal itself to them, proof of an afterlife might not be everything Matt dreamed of.

All Rob wanted was a normal life. She almost got it, too: a husband, two kids, a nice house in the suburbs. But Rob fears for her oldest daughter, Callie, who collects tiny bones and whispers to imaginary friends. Rob sees a darkness in Callie, one that reminds her too much of the family she left behind. She decides to take Callie back to her childhood home, to Sundial, deep in the Mojave Desert. And there she will have to make a terrible choice.

In a boarded-up house on a dead-end street at the edge of the wild Washington woods lives a family of three. A teenage girl who isn’t allowed outside, not after last time. A man who drinks alone in front of his TV, trying to ignore the gaps in his memory. And a house cat who loves napping and reading the Bible. An unspeakable secret binds them together, but when a new neighbor moves in next door, what is buried out among the birch trees may come back to haunt them all.

Fresh out of rehab, Mallory Quinn takes a job as a babysitter for Ted and Caroline Maxwell. She is to look after their five-year-old son, Teddy. Mallory immediately loves it. She has her own living space, goes out for nightly runs, and has the stability she craves. And she sincerely bonds with Teddy, a sweet, shy boy who is never without his sketchbook and pencil. His drawings are the usual fare: trees, rabbits, balloons. But one day, he draws something different: a man in a forest, dragging a woman’s lifeless body.

Ana and Reid needed a lucky break. The horrifically complicated birth of their first child has left Ana paralyzed, bitter, and struggling: with mobility, with her relationship with Reid, with resentment for her baby. That's about to change with the words any New Yorker would love to hear—affordable housing lottery. They've won an apartment in the Deptford, one of Manhattan's most revered buildings. Reid dismisses disturbing events and Ana’s deep unease and paranoia as the price of living in New York—people are odd—but he can't explain the needle-like bite marks on the baby.

In the summer of 1994, psychologist Daniel Hill buys a rustic farmhouse nestled in the rolling hills of West Virginia. Along with his wife and teenage daughter, the family uproots their lives in Ohio and moves south. They are initially seduced by the natural beauty of the country setting. That soon changes when they discover a hidden room in the basement with a well, boarded shut and adorned with crucifixes. Local legends about the previous owner being an exorcist come to light, but by then, all Hell has broken loose.

St. Vincent's Orphanage for Boys. Turn of the century, in a remote valley in Pennsylvania. Here, under the watchful eyes of several priests, thirty boys work, learn, and worship. Peter Barlow, orphaned as a child by a gruesome murder, has made a new life here. As he approaches adulthood, he has friends, a future...a family. Then, late one stormy night, a group of men arrive at their door, one of whom is badly wounded, occult symbols carved into his flesh. His death releases an ancient evil that spreads like sickness, infecting St. Vincent's and the children within.

Thirteen-year-old Ben is sent to a remote reform program for troubled teens by a juvenile court judge. But when he arrives at the camp, located on the edge of the vast wilderness of northwestern Montana, he immediately recognizes that there is something off about the counselors. They’re too friendly and upbeat…yet Ben can tell there’s an undercurrent of menace. As he gets to know the boys in his cabin, he soon discovers that they each have far more going for them than whatever crime landed them there.

As the daughter of spiritualists, Mara's childhood was filled with séances and scam mediums. Now she's ready to start over with her fiancé, Neil, far away from the superstitions she's learned to loathe, but her past isn't willing to let her go so easily. And neither is Blackwood House. When Mara and Neil purchased the derelict property, they were warned that ever since the murder of its original owner, things had changed. Strange shadows stalk the halls. Doors creak open by themselves. Voices whisper in the night. And watchful eyes follow her every move.

Emma Carpenter lives in isolation with her golden retriever Laika, house-sitting an old beachfront home on the rainy Washington coast. Her only human contact is her enigmatic old neighbor, Deek, and (via text) the house’s owner, Jules. One day, she reads a poorly written—but gruesome—horror novel by the author H. G. Kane, and posts a one-star review that drags her into an online argument with none other than the author himself. Soon after, disturbing incidents start to occur at night.

Lifestyle journalist Katrine escaped past traumas by moving to a coast renowned for seaside holidays and natural beauty. But when a vast hoard of human remains and prehistoric artifacts is discovered in nearby Brickburgh, a hideous shadow engulfs her life. Helene, a disillusioned lone parent, lost her brother, Lincoln, six years ago. Disturbing subterranean noises he recorded prior to vanishing, draw her to Brickburgh's caves. A site where early humans butchered each other across 60,000 years. Upon the walls, images of their nameless gods remain.

"Mom seems off." Her brother's words echo in Sam Montgomery's ear as she turns onto the quiet North Carolina street where their mother lives alone. She brushes the thought away as she climbs the front steps. Sam's excited for this rare extended visit, and looking forward to nights with just the two of them, drinking boxed wine, watching murder mystery shows, and guessing who the killer is long before the characters figure it out. But stepping inside, she quickly realizes home isn’t what it used to be.

A strange plague called the "Gets" is decimating humanity on a global scale. It causes people to forget - small things at first, like where they left their keys... then the not-so-small things like how to drive, or the letters of the alphabet. Then their bodies forget how to function involuntarily - and there is no cure. But now, far below the surface of the Pacific Ocean, deep in the Marianas Trench, an heretofore unknown substance hailed as "ambrosia" has been discovered - a universal healer, from initial reports.

When Margaret and her husband Hal bought the large Victorian house on Hawthorn Street—for sale at a surprisingly reasonable price—they couldn’t believe they finally had a home of their own. Then they discovered the hauntings. Every September, the walls drip blood. The ghosts of former inhabitants appear, and all of them are terrified of something that lurks in the basement. Most people would flee. Margaret is not most people. Margaret is staying.

Twenty-five years ago, Maggie Holt and her parents, Ewan and Jess, moved into Baneberry Hall, a rambling Victorian estate in the Vermont woods. Three weeks later they fled in the dead of night, an ordeal Ewan later recounted in a nonfiction book called House of Horrors. His horror memoir of ghostly happenings and encounters with malevolent spirits became a worldwide phenomenon, rivaling The Amityville Horror in popularity — and skepticism.