House of Dark Shadows

Willie Loomis, the Collins family handyman, searches the mausoleum for treasure and accidentally releases Barnabas Collins, a vampire of 175 years. Barnabas immediately asserts control over Willie, turning him into an unwilling ally and servant.

Shortly after his release, Barnabas attacks Daphne Budd, the secretary to Elizabeth Collins Stoddard. Jeff Clark discovers her condition and takes her back to Collinwood, where Dr. Julia Hoffman attends to her injuries.

Barnabas arrives at Collinwood and presents himself as a long-lost English cousin. The family is intrigued; Elizabeth's sister and others welcome him, while Carolyn Stoddard and Professor Stokes remain skeptical.

Barnabas moves into the Old House and proposes hosting a ball in his honor to win the family's acceptance. The plan stirs curiosity and unease among the residents.

On the night of the ball, Carolyn Stoddard is bitten by Barnabas as she gets ready. The bite marks her for life and foreshadows the danger he poses to the family.

Carolyn dies soon after the bite, and a funeral is held for the young woman. Dr. Hoffman analyzes Carolyn's blood and detects traces of the same unknown virus found in Daphne Budd's blood, prompting Professor Stokes to suspect a vampire.

Carolyn rises as a vampire and menaces David Collins. She later bites her fiancé, Todd Blake, revealing the extent of Barnabas's influence over the attacks.

Professor Stokes shares his vampire theory with Julia, who is initially skeptical but soon becomes an ally after seeing the evidence. The family begins to realize there may be truth to the danger they face.

Julia convinces Barnabas to let her treat him with a modern serum, granting him daylight mobility and reducing his need to feed on humans. This shift changes the balance of power at Collinwood and draws him closer to Maggie Evans.

As Barnabas adjusts to a new, partially human condition, he spends more time with Maggie Evans, the governess who resembles his long-lost Josette. He wooes her and tries to keep her from leaving Collinwood.

Overcome with jealousy, Julia administers an overdose of the serum, causing Barnabas to age to his true 175-year-old form. In a fit of rage, Barnabas strangles Julia to death.

With his power restored, Barnabas bites Maggie Evans once more and abducts her, intending to make her his bride. The pursuit to stop him begins in earnest.

Jeff and the others pursue Barnabas; Roger Collins and Professor Stokes are killed and turned into vampires, only to be destroyed by Jeff. The truth about Barnabas's vampire identity becomes widely known among the family.

In a ruined church, Willie Loomis makes a final stand to help Jeff and Maggie escape. He is mortally wounded, and Jeff shoots Barnabas in the back, driving a crossbow bolt through the vampire's chest. Barnabas dies, and Maggie is rescued.

In a post-credits moment, Barnabas's body collapses and transforms into a bat, flying away into the night. The fate of the vampire remains symbolic as the sequence closes.