Megan Larsen doesn't think she's crazy, but she sure has been acting strange. She's been waking up in the middle of the night convinced she's seen a bright light only to find her house in darkness and losing both sleep and self-confidence in the process. All of this makes it hard for her to focus on her work as a lawyer--a particular problem now that her review for a possible partnership is coming up. Megan wants Jane, her next-door neighbor, to determine whether or not she's sane. No sooner has Jane suggested a few common-sense steps to help answer Megan's question and identified a possible biological cause of her troubles and three men in her life who might be gaslighting her--an old friend and colleague, an ex-boyfriend, and a disastrous online date--then Megan vanishes. Her father, high-powered attorney Edwin Larsen, is unconcerned (some father!), but Jane presses on, counting on the fact that she's on much better terms with Detective Tony Alvarez than with Megan's father, realtor, or security provider.