Spoilers for spookiness below.
- The opening credits alone manage to give some the shudders.
- Bloody Mary, there was an awfully chilling scene where a girl is walking through a dark hallway trying to avoid every reflective surface which Bloody Mary may appear from, she thought she was safe when she got to the lift, only to see Bloody Mary right behind her from an adjacent mirror as the lift door slowly closes.
- An episode featured a ghost with a breathing mask in a morgue. If you attempt to talk to it, it rasps unintelligibly at you and then has an epileptic fit while bleeding from the eyes. Which are taped shut.
- Another ghost called Sally Stitch used a terminally ill girl in a hospital to send chain mail that killed people. The bad part was that there's a doll with stitched-shut eyes and mouth that is a cutesy representation of the real Sally Stitch, a Victorian woman who had her eyes and mouth sewn shut for gossiping.
- That faceless child... It had a completely blank face, no mouth, no nose, no eyes, no brows... Completely empty, except for the two golf ball-shaped indents where the eyes should be. And it giggled.
- The season 1 villain, The Dark Man, who was collecting souls afraid of going into the afterlife for some unknown nefarious purpose, which was not concluded until the last season.
- While she rapidly becomes a major woobie, Emily from "Drowned Lives" is fairly creepy early on, especially with her glowing eyes and Voice of the Legion...Emily: DON'T WAKE UP MY MOTHER! SHE'S SLEEPING!
- From "Free Fall", they discover that the passengers and crew of a plane have died, and that it is about to crash in or near Grandview. Melinda tries to warn everyone at the last second, but is drowned out by the shriek of jet engines as the plane flies low overhead. Once the plane is out of view, there is a brief deafening silence, then the violent explosion of sound as the plane crashes nearby.
- The Tattooed Man, one of the more violent, aggressive spirits.
- The marching army of polio children in handmade animal masks from the series finale.
- Jamie Bamber's thoroughly convincing performance as a zombie in "The Walk In". Kudos to the makeup department.
- "Old Sins Cast Long Shadows". Specifically, the main antagonist of the episode, Madame Greta, who tricks dying children into coming to her house so she could sacrifice their spirits to the Shadows. She also threatens Melinda that she always knows where her son is.
- Shane Carson, the main villain of "No Safe Place", is a rare yet effective example of how a living person can be more terrifying than a ghost.
- At first we are led to believe that Shane is being haunted by Colleen Finn, who supposedly talked him while she was alive. We later learn that it was actually Shane who stalked Colleen and this was what led to her death; when she thought he was trying to break into her apartment, she accidentally fell down a stairwell and broke her neck. This also causes her to have an unsettling neck twitch as a ghost.
- Shane did worse than stalk Colleen. He isolated her from friends and family by essentially making it too much trouble for her to be supported — spreading lies about her, hacking their bank accounts, invading their privacy in other ways etc. When Shane sets his sights on Melinda, she gets a taste of what Colleen had to put up with when he makes it look like her friend Delia lied on her son's application to get him into a private school.
- At one point, Colleen is trying to scare Shane at his office only for him to laugh off her attempts. Normally, a ghost failing to scare a human would be an impressive moment, but given what we know about Shane and Colleen, it only drives home just how twisted Shane is and how, even as a ghost, Colleen is still helpless against him. It is especially disturbing when Colleen talks about how he drove her last boyfriend away from her and then Shane's computer shows pictures of Melinda, revealing that she is his new target.
- After exposing him for a stalker and helping Colleen get closure with the detective who was in love with her, it seems all is well for Melinda. Then Shane shows up in the basement of the antique store. At that moment Jim calls Melinda to inform her that Shane is dead from an overdose — the man killed himself just to torment Melinda forever and if not for the dark spirits taking him away, she would never have been free from him.
