Alan Patterson (Leslie Nielsen) is a businessman who meets a couple of mentally disturbed people, Merle Jenkins (George Grizzard), and Lily Hanson (Natalie Trundy), whose envy of him and his life becomes obsessive. This, along with the next five episodes in broadcast order, was produced by Fletcher Markle.

Connie Walworth (Constance Ford) is a widow who is shocked to learn that her late husband's Uncle Archer did not leave a will, and thus left no inheritance for her. She learns from their family lawyer, Mr. Sinclair (Jay Jostyn) that her mother-in-law, Myra (Harriet MacGibbon) will receive everything by default. Connie blackmails Myra to ensure she gets a cut of the money.

A little girl, Tessa Kilburn (Terry Burnham), shoots a man, Charles Mowry (Charles Cooper), to death at her family's vacation house. Everyone runs in and tries to figure out why she did it, but she says that her muteness has a purpose. It turns out that her father Douglas' (Shepperd Strudwick) fiancée, Sylvia Walsh (Mona Freeman), cooked up a scheme with Charles and his brother Paul (Berry Kroeger) to get Douglas' money. Charles threatens to expose them, and Sylvia shoots him, and frames Tessa for the murder.

An actress, Rose French (Mary Astor), gets thrown out of a bar and nearly hit by a car, and is arrested. Frank Clyde (Lin McCarthy) runs a rehabilitation center for alcoholics and helped Rose in the past. Frank and her landlord, Annie Cushman (Loie Bridge), are surprised to learn she is going to La Mesa, California, to take a job as a housekeeper. Shortly after, they learn that Rose was found dead in the garden of a stranger's home, and it turns out that the job was actually a really unusual acting job.

Three boys who grew up in a bad neighborhood try to become successful adults, but they get mixed up with the Mafia. Lou Adams (Everett Sloane) is a consigliere, Cesar Romano (Frank Silvera) is a crime syndicate boss, Tony Romano (John Marley) is a respected doctor.

Duncan Corey (Rip Torn) is set to inherit his brother's valuable land and the house on the property, with the stipulation that he has to spend the night there and live there for one year. If he fails to follow those rules, the inheritance will go to his cousins, Rachel (Patricia Barry), and Oliver Judson (Richard Anderson). First episode, in broadcast order, produced by William Frye.

In a resort town being plagued by a serial murderer, Mr. Freitag (Martin Gabel), a lonely school teacher, sits in a boat, the "Suzie-Tee", and is struggling to drown a woman by pushing her head under water as she tries to fight to save herself. The incident is eventually classified as an accident, but there are skeptics that make a push to probe deeper. Produced by William Frye.

Alice Page (Myrna Fahey) is a newlywed, going to meet her husband, Anthony's (Rhodes Reason), family for the first time. She learns several unsettling things about her new husband and family. Produced by Fletcher Markle.

Clayton Mace (Boris Karloff) is a fake mentalist who puts on shows where he claims to see the future from a disco ball inside of a crystal ball. One night, he predicts that a boxer, Tommy Tims, is going to die in a fight, which turns out to be true. He tried to leave to warn the manager and Tommy about what he saw to warn them, but he is restrained by a couple of men, and Roscoe Burton (Alan Caillou) says he will go warn them on his behalf. Roscoe lied and never went to warn them; instead, he makes a bet on the fight based on his knowing of the death, which causes outrage when everyone thinks Clayton orchestrated it. Produced by William Frye.

Harry Elser (Elisha Cook Jr.) is a mentally disturbed man who plots an assassination of a candidate for Mayor, Walker Wylie (Conrad Nagel). Under the guise of being a maintenance man, Harry gets into Walker's office. Harry was placing a bomb in Walker's desk, but he is busted, but gets away before he can be stopped. He hides in a closet, and when the coast is clear, he gets on a crowded elevator and puts the bomb in a woman, Jane Kimball's (Whitney Blake) purse. Harry is hit by a truck, but he tells the police about the bomb before he dies. The police race against the clock to get it, before it goes off at 11pm. First episode, in broadcast order, produced by Maxwell Shane.

A group of thugs are looking for Bill Logan, with orders to assassinate him when they find him. In a case of mistaken identity, they target a recovering alcoholic, Burt Lewis (Jack Carson), who fits the description of Bill Logan. As the story unravels, not all is what it seems, and Burt does not know whom to trust. Produced by Maxwell Shane.

Ray Kenton (Joe Maross) is deep in gambling debt, and only has 24 hours to pay it off, or he will be killed. Ray's wife, Ruth (Beverly Garland) has a savings account, but refuses to give Ray the money, because she is tired of his gambling. Elsewhere, a serial murderer, dubbed the "Silk Stocking Strangler" (Meade Martin), has just left another victim, and later, Ray gets him to help get the money from Ruth by plotting her murder. Produced by Maxwell Shane.

Television writer Sam Lynch (Mort Sahl) overhears two men, Mr. Clark (Werner Klemperer) and 'Baby' Hoffman (Julian Burton), plotting the kidnapping and possibly the murder of a socialite, Kay Salisbury (Sue Randall), for a ransom demand of $100,000 from her father, Charles (Frank Albertson). Sam tries to mind his own business, as if he never heard anything, but it's too late— Mr. Clark already saw him, and he gets dragged into the plot. Final episode, in broadcast order, produced by Fletcher Markle.

Dirk Van Prinn (Henry Daniell) invents spectacles, emblazoned with the word "Veritas" (Latin for "truth"), and the glasses are meant to show the wearer the truth about themselves and others. Horrified at what he sees, Val hangs himself. Years later, while conducting a salvage mission at Dirk's old house, a man finds the spectacles, and they cause death and destruction in his life. The spectacles continue to pass from person to person, a veritable curse in the eye of the beholder, until an afflicted person destroys them. Produced by William Frye.

Gil Thrasher (William Shatner), and his wife, Marcia (Joanna Heyes), are escorted to their new home, a mansion in New England, by their realtor, Adam Talmadge (Russell Johnson), and his wife, Liz (Elizabeth Allen). The house was formerly occupied by an old woman, Laura Bellman (Ottola Nesmith), whose husband Jonah built the house for her in the 1860s. When she was young, Laura (Donna Douglas) became obsessed with admiring her reflection in a room in the attic that was full of mirrors, eventually falling through one to her death as an old woman. The Thrashers see Laura, and other ghosts in the mirrors now, trying to lure them to similar fates. Produced by William Frye.

Thomas Edward Griffith (Murray Matheson) lies his way into marrying way out of his league to a wealthy socialite, Frances Abercrombie (Sarah Marshall). Thomas later learns Frances lied too, and she married him for money, as well. To Thomas' dismay, his in-laws move in and he quickly stirs up a remedy to be rid of them all. Produced by William Frye.

Noel Hudson (Guy Stockwell) becomes entangled in a Tangierian drug smuggling scheme and is forced at gunpoint by some evil men to smuggle heroin. Noel manages to take the heroin and make a break for it, but when he completely goes missing, his elder brother, Darryl (Philip Carey), begins a frantic search for him. Produced by Maxwell Shane.

Edith Landers (Susan Oliver) is a wealthy woman whose life is controlled by her domineering Uncle Phillip (Vaughn Taylor). Edith meets a charming con artist, Ralphie Teal (Larry Blyden). Ralphie falls in love with Edith, but soon finds the tables have turned, as a murder plot unfolds. Produced by Maxwell Shane.

A detective inspector, Harry Roberts (Kenneth Haigh), for the Scotland Yard is summoned to Dark Falls, Wales to investigate the murder of a man by a hay-fork and a bill-hook. When another murder occurs, superstitious locals shift their focus to Harry's wife, Nesta (Audrey Dalton), believing she is a witch. Produced by William Frye.

An intruder breaks into the home of Ann Merriweather (Bethel Leslie), and fails his attempt to kill her. She goes to her neighbor and attorney, Howard Yates (James Gregory) for help with the invasion, and so he can represent her husband, Charles (Ross Elliott), who is charged with murder when a dead body is found in the trunk of his car, whom Charles claims to know nothing about. Produced by Maxwell Shane.

Lt. Jim Wagner (Nehemiah Persoff) is investigating a series of child murders committed by a killer referred to in the press as the "Mad Dog". The likeness of the killer fits that of a local dishwasher, Ohrback (Robert Middleton), and they eventually find enough evidence and witnesses to arrest him. The investigation shifts to a new suspect, Mr. Merriman (Thayer Roberts) when Ohrback's blood does not match a sample at the crime scene, and evidence of the broken leg of a rare Italian doll is found. Produced by William Frye.

Robert Penrose (Ronald Howard) is headed to the English countryside for his bachelor party with his butler, Jeremy Teal (Torin Thatcher). While en route, they are accosted by a fiendish pair, Master Styx (Richard Kiel) and Squire Moloch (Henry Daniell), at gunpoint, and Robert offers to sign over .5 million pounds to them. At an estate in the moors, Robert learns some disturbing information about his father. Produced by William Frye.

Dr. Frank Cordell (Robert Vaughn) is conducting chemical experiments in his laboratory when he stumbles on to a strange gas that turns him into a violent homicidal maniac. The race is on to counteract the effects and keep him from killing again. Produced by Maxwell Shane.

The Extra Passenger: Simon (Richard Lupino) plots the death of his wealthy Uncle Julian (Terence de Marney), who unbeknownst to him is a warlock.
A Terribly Strange Bed: Collins (Robin Hughes) wins big at the roulette table in a casino and he is convinced by The Hussar (Reginald Owen) to spend the night there, where he is nearly crushed by the canopy of the bed.
The Mask of Medusa: The police are on a manhunt for the "Latent Strangler", Shanner (Michael Pate). He hides out in a wax museum, where he meets the owner, Kriss Milo (John Abbott), who shows him all around his exhibit of killers who turned into figures after looking at the mask of medusa.

Bandleader Eddie Wilson (John Ireland) attempts to revive his career by using voodoo music, but after a boost, things take a turn for the worse. Final episode, in broadcast order, produced by Maxwell Shane.

Larry Weeks (Larry Pennell) arrives home to a surprise visit from his brother, James (Edward Platt). James' cheating wife has been strangled to death. Larry helps James frame her lover, Sid (Steve Mitchell), for the murder. This episode was produced by William Frye, as are all Thriller episodes from this point forward.

In modern day (1960s) New York, a series of murders have occurred that fit the M.O. of Jack the Ripper from 70 years prior. A Scotland Yard psychologist, Sir Guy (John Williams) is an expert on the Ripper, and believes the current murders were done by the original killer, and who he claims had received immortality through blood sacrifice. Capt. Pete Jago (Edmon Ryan) and police psychologist Dr. John Carmody (Donald Woods) are investigating on case, and are skeptical of Guy's claims.

Hector Vane (MacDonald Carey) is an artist who lives with his wife, Marie (Joan Tetzel) in a dump of an apartment. Low on funds, he goes to a pawnshop owned by a miser, Mr. Spengler (Robert Cornthwaite), but is now run by a mysterious pawnbroker (John Emery), who offers Hector three months of fame and fortune in exchange for his soul. If Hector paints a portrait of a human soul before the 90 days are up, he can get his soul back, but trouble ensues.

Frank Logan (Edward Andrews) is fed up with his wife Louise's (Patricia Berry) numerous affairs, and plots to kill off all of her lovers one by one.

A lonely child, Priscilla (Gina Gillespie) misses her guardian, Mr. George (Les Tremayne), who died. Mr. George remains present for her like a guardian angel. Priscilla has inherited property and a large sum of money that her three greedy Leggett cousins, Edna (Virginia Gregg), Jared (Howard Freeman), and Adelaide (Lillian Bronson), are after. The cousins plot an accidental death for Priscilla, but Mr. George's voice and guidance from beyond steers Priscilla away from peril.

A concert pianist, Vladimir Vicek (Guy Rolfe), obsessively covets the skills of a rival, Carnowitz. When Carnowitz dies, Vladimir and an associate, Gafke (Reggie Nalder), desecrate his grave to steal his large hands, in order to play a concerto specifically made for someone with large hands.

Professor Harry Langham (Lloyd Bochner) is writing his thesis on 18th-century magician/sorcerer, Count Cagliostro (Henry Daniell), and goes to France to buy a mirror the Cagliostro once owned that has its glass painted over. Cagliostro is supernaturally trapped in the mirror and wants to use Harry's body to live again.

A magician, Mario Asparos (Harry Townes), uses a book he inherited from his dead uncle, Radan, to invoke a demon, despite his wife Monika (Ilka Windish) and his friend Toby Wolfe (Henry Silva) trying to stop him.

Brothers Timothy (Brandon De Wilde) and Johnny Branner (David Whorf) break down in their car in the Deep South. As they go to look for help, Johnny is caught in a flock of pigeons. They stumble onto the Blassenville plantation, and decide to spend the night there. Johnny becomes entranced by an unseen force and he goes after Timothy with a hatchet. Timothy runs from the house and passes out, and is found by a hunter Jacob Blount (Ken Renard), who summons Sheriff Buckner (Crahan Denton). Timothy explains what he saw, saying he believes Johnny is dead. Buckner takes Timothy back to investigate the house and find a dark and supernatural family secret.

Beatrice Graves (Natalie Schafer) causes concern for her nephew, Paul (William Shatner) when she buys an old painting of The Grim Reaper, thought to be connected to the mysterious deaths of its previous owners. Beatrice ignores this concern, but then sees evidence for herself that it may be true.

A wealthy, aging, concert pianist, Mildred Adler Beaumont (Judith Evelyn) has a vision of herself in a coffin, with organ music in the background. She is unable to convince her husband, Eric (Tom Helmore), and her sister Lydia Adler (Adele Mara) of what she has seen, and uncovers a sinister plot against her.

In 1875 France, Robert Lamont (Alejandro Rey) is convicted of murder and is set for execution by the guillotine, but he has discovered a loophole that could help him avoid death if his executioner, Monsieur de Paris (Robert Middleton), were to die before he can be executed. Robert comes up with a plan and enlists his wife, Babette (Danielle De Metz), as an accomplice.

Edward Stapleton (Sidney Blackmer) is a cataleptic millionaire who survives having been buried alive. His loyal long time doctor, Dr. Thorne (Boris Karloff), helps him take precautions to avoid death again. Edward finds himself a scheming bride, Victorine Lafourcade (Patricia Medina), who plans to get him gone gone for good, so she can run off with his money, and her lover, Julian Boucher (Scott Marlowe).