Salem's Cove was built upon a spiritual nexus. It's up to the two witnesses to keep evil in check or face apocalyptic events on a global scale.

Unexplained evil acts have been happening since Salem's Cove was founded after the Salem Witch Trials. Sheriff Grey and LT Gibbs greatest fears are about to be unleashed, not only to the people of Salem's Cove but to the rest of the world. (Salem's Cove (Season 1 - 13 Episodes) is a prequel to the feature film Return To Salem's Cove)