Something sinister lurks behind the perfect homes and well-manicured lawns of Mulberry Grove. Wealthy tech investor Jack Harlow, known to the FBI as Mad Jack, has been running a personal development program for the past ten years. Locals call it a cult. Few leave, and those who try, end up dead under mysterious circumstances. Six couples in all over the last five years.

FBI Agents Kate Walsh and Declan James are sent in undercover, posing as a married couple interested in the program. Out of her normal FBI profiler role, Kate is challenged by Jack Harlow's instant recognition of her insecurities. Even her relationship with Declan is under the microscope.

Kate and Declan must work together to figure out who is friend and foe in the tight-knit community where nothing is as it seems. When Kate is targeted similarly to the other women, she and Declan's lives are on the line. Can the two stop a killer before they become the next victims or will Jack Harlow continue to wreak havoc in the community?