Continuity mistake: When Angelique traps Barnabas in the coffin for the second time, there is a separate lid to the coffin. But by the time Barnabas is in the cemetery, hinges have suddenly appeared on it. (01:24:05 - 01:25:45)
Continuity mistake: As the Collins watch the manor burn down, two cars can be seen in front of the house. A couple of shots later, the cars have vanished. (01:40:50)
Continuity mistake: After Angelique kisses Barnabas, the lipstick she leaves on his face disappears and reappears between shots.
Continuity mistake: When Barnabas stops the disco ball from landing on David, he is set on fire. Willie then chucks a pail of water on him to stop him burning. The next shot shows the bucket Willie holds and there is no trace of water, nor is the bucket wet, even though he'd just used water from the pail to throw at Barnabas. (01:21:00)
Continuity mistake: In the aerial sequences of the Amtrack train near to the start of the file, most of the shots shows 2 engines (front and rear) plus 4 carriages. In two of the shots, you can see 5 carriages.
Continuity mistake: When Angie kisses Barnabas in the drawing room, there is a small lipstick smudge above his upper lip. In the next shot, the smudge is much larger and it is under his lower lip.
Continuity mistake: As Barnabas approaches Dr. Hoffman, he passes an IV bag full of blood. Quick shot to Hoffman, then back to Barnabas, and he passes the IV bag again.
Answer: It's unknown. The original intention was to make Dark Shadows into a film franchise and that question probably would have been answered in the sequel. However, there have been no additional films made.
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