When best friends Hannah and Scarlett meet Thomas in college-the chemistry is instantaneous. They grow closer while playing the Daring Game, where each dare is riskier than the last. As the trio's friendship begins to cross boundaries between the platonic and the illicit, jealousy and secrets quickly develop. As tensions between the three grow, so do the stakes in the Daring Game, resulting in tragedy with Scarlett's final dare to Thomas. When Thomas gets expelled from school and leaves without a trace, it seems like the Daring Game has finally ended. Sixteen years later, Hannah is unhappy in marriage and in life. That is, of course, until she gets a mysterious letter about the Daring Game from none other than Thomas himself. With Scarlett out of the picture, and a renewal of the dangerous game, the sparks begin to fly between them once more. Until the day Hannah and Thomas are called to the secret meeting place of the Daring Game, where they're welcomed by a single dare-'to tell the truth.' Someone else has joined the game and knows about their affair, going as far as leaving a cryptic message in Hannah's house: Don't You Dare. Hannah's list of suspects is long: Could it be her nosy neighbour, Libby, who has a few secrets of her own? Or did her husband plan this as revenge for the torrid affair? Is Scarlett back and ready to play again? The truth may set Hannah free-but only if she dares to risk everything she knows and loves.