Lilli Masters, a photojournalist, arrives in Grayrocks, a resort town on Long Island, eager to photograph the rambunctious Labor Day activities.

When she checks into Baywatch Inn and discovers that two women are missing, she promises Gram Jenkins, the innkeeper, to look for them. That turns into an unexpectedly pleasant task when handsome New York City detective Zack Faraday, visiting for the weekend, offers to help.

Soon after Lilli photographs the area surrounding the Montauk Steps, a ceremonial site sacred to the Montauk Indians, a mysterious stranger destroys her work. As his violent behavior escalates, Lilli is convinced that her photographs offer clues to the whereabouts of the missing women and that her fate is connected to theirs. Caught up in the ensuing manhunt and running for her life, Lilli struggles to save herself and the people she has come to care about.