In a small town in Massachusetts, a group of friends, fascinated by the internet lore of the Slender Man, attempt to prove that he doesn't actually exist - until one of them mysteriously goes missing.

At a birthday party in 1968 New York, a surprise guest and a drunken game leave seven gay friends reckoning with unspoken feelings and buried truths.

When a popular teen dies, her best friend basks in the glow of the social media attention, while their rival seeks to avenge the past, and uncover the truth behind the mysterious death.