Revealing mistake: 1970: When the sheriff knocks, Jeb opens the antique shop door and the jangling shop bell falls off and crashes to the floor. They pretend that nothing happened and go on with their lines.
Audio problem: In several episodes, there is a shot of the grandfather clock in the downstairs hall. When the camera comes in for a close-up of the face of the clock, a chime can be heard. It is the Westminster chime, which normally sounds on the quarter hour (4 notes), the half (8 notes), the three-quarter (12 notes) and the hour (16 notes plus the number of hours). However, on several occasions, the clock is off-strike, either by the number of notes it chimes or chiming when it normally would not (for example, at 11:20).
Other mistake: 1969: David blunders his line to Cousin Amy: "Don't feel too bad, Amy. I don't like to feel my relatives, err, I don't like to see my relatives."
Revealing mistake: 1967: Dr. Woodward struggles with a stuck zipper on an oxygen tent. When the prop refuses to cooperate, he makes a disgusted sound and adlibs to his companion, "Zip that up, will you, Julia?" Then he hurries out, leaving a bewildered Julia to deal with a supposedly critical patient.
Revealing mistake: 1795: Ben, complaining that Angelique is always watching him, backs into a large, tall tree trunk in the cemetery. The "tree" wobbles and sways when he bumps it.
Revealing mistake: 1897: Quentin walks away from Trask and exits through the door under the stairs. Unfortunately, that door was undersized, and David Selby was 6'2" tall. Quentin bangs his head on the doorframe hard enough to produce an audible thump.
Visible crew/equipment: 1967: During the closing credits, a crew member walks by outside the supposedly-second-story window of Josette's bedroom - twice.
Revealing mistake: 1990s: When Barnabas and Julia time travel into the 1990s, they find Mrs. Johnson's body tied to a tree. While a crazed Carolyn accuses them of killing her, the "corpse" blinks several times.
Other mistake: 1966: Standing over the doctor's microscope, Burke blows his line to Woodward: "When you examine it under the microphone, it doesn't show any mystery at all."
Audio problem: 1840: During a graveyard scene, the village bells are tolling the hour, but someone forgets to kill the sound effects tape. The chimes strike sixteen-o'clock.
Revealing mistake: David is trapped in the Collins mausoleum, but doesn't yet know about the moving stone in the stairs that will allow him to open the door. At one point he moans and lies down on the stairs, which causes the "heavy" stone to flop around. He gently moves it back.
Revealing mistake: 1967: The dying Dr. Lang fumbles with a reel-to-reel recorder, making a tape that we'll hear over and over again later on. Only he "records" his message with the machine turned off: the reels aren't moving.
Other mistake: 1897: Barnabas forgets his verbal 'shopping list' of five potion ingredients as he delivers it to a servant. He says, "Now go into town and collect Magda's herbs and, uh, herbs and, well whatever else it is she needs."
Continuity mistake: The newly-cured Barnabas, wearing a red striped bathrobe, screams when Dr. Lang opens the drapes to let the sunlight in. When the same scene is recapped the next day, Barnabas is suddenly wearing a solid blue bathrobe.
Revealing mistake: 1968: Jeff Clark runs terror-stricken out of a cemetery and accidentally stumbles over a tombstone. The 'granite' marker falls over with a hollow thud.
Revealing mistake: 1795: When an angry Lt. Forbes rushes out Collinwood's front door and tries to slam it, the flimsy set door not only doesn't slam, it bounces back open. The supposedly in-a-hurry lieutenant comes back and gently re-closes the door.
Revealing mistake: 1968: A shot of Barnabas and Julia taken through the small window in the cellar door apparently obscured Jonathan Frid's view of the all-important red light. Obviously thinking himself off-camera, Frid took a moment to clean the inside of one nostril with his index finger.
Factual error: 1968: The basement's brick wall crumbles to reveal Trask's skeleton hanging in the alcove. Only it shouldn't be. Bodies do not remain assembled once the flesh and sinew are gone. Trask's remains ought to be a large pile of bones on the floor.
Other mistake: 1897: Valerie Collins is supposed to praising Collinwood. But instead, she gushes, "Hollywood. I never imagined I'd see it."
Suggested correction: I listened to this carefully and it is incorrect. She does, in fact, say Collinwood. The enunciation is just a bit muddled.
Still sounds like "Hollywood" to me. But the correct name, in any case, is "Collinwood," not "Collonwood."
Other mistake: 1840 Parallel Time: Julia Collins suffers from a bad case of tangle-tongue syndrome when she says, "Don't you think that I would like to help Bramwell gill the coast of Brutus Collins?"