The Sins of Sisters — Emma Bradley

Life outside the citadel is busy and lavish, but Molly still feels like something is missing. Stuck inside the citadel, Talie is longing to be anywhere else, but she can't leave Sammy behind. When dark rumours begin circulating about Phoenix's new rule and rebels begin fighting back, all eyes return to the well beneath the citadel and the power it holds. Once again on different sides, Molly and Talie need to figure out where they both stand, and fast.