Hysterical (1982)

"It'll snap your mind."

Frederic Lansing is a writer who hopes to find inspiration while vacationing in Hellview, Oregon; however, the lighthouse in which he's staying is haunted by the ghost of Venetia, who had killed herself 100 years ago and now wants to use Lansing as a vessel for her dead husband, Captain Howdy. When Howdy's ghost starts killing people, two bumbling scientists are brought in to investigate the history of the lighthouse and solve the case.