The Hollow Oak

The motive for Darla's revenge stems from several events that led to her eventual death and subsequent haunting of the campgrounds. Firstly, her mother was executed by the townsmen for being accused of witchcraft, which likely instilled a deep sense of anger and resentment toward the community. Additionally, Darla's heart was broken when Tim, the man she loved, left her after impregnating her. This likely caused her immense emotional pain and trauma. When she sees Tim giving her friend Katelyn a necklace, which he intended to give to her before he left town, Darla feels betrayed and seeks revenge.

To carry out her plan, Darla secretly involves herself in a coven of witches and plans to poison them, including Katelyn. She steals Katelyn's diary and writes a passage in it, making it appear as if Katelyn is planning to murder the coven and Darla, hoping to pin the murders on her. However, Darla's plan backfires, and the girls defend themselves, killing Darla and throwing her body into the lake. Decades later, Spencer, a girl who finds the diary believes that Katelyn White is the one who killed the coven.

Darla's revenge was motivated by her desire to seek justice for her mother's execution, her broken heart, and her belief that Katelyn White was responsible for her exclusion from the coven and her eventual death.