“In the world of thrillers, few conceits are more alluring than a ‘mostly harmless’ habit gone terribly awry. Such is the premise in Jennifer Sadera’s addictive I Know She Was There, where protagonist Caroline Case’s proclivity for sidewalk-spying on her wealthy neighbors turns into her own living nightmare. Sadera’s deeply psychological novel, echoing nicely to Rear Window, has Caroline guessing not only what she saw, but whether she saw it at all, and her struggle becomes ours through effective first-person narration. An impressive and thrilling debut…Sadera is an author to watch.”