The Sprite Sisters: 4 sisters, 4 elements, 4 powers. Fire. Water. Earth. Air. The Mystery of the Locked Room is the 8th title in the bestselling Sprite Sisters series, which has had sold nearly 400,000 copies. Snow is about to fall at the end of the autumn term at Drysdale's School. Flame is agonising over her relationship with Quinn, while Marina is busy rehearsing for her leading role in the school play. Late one afternoon, Ash's intuition is alerted by the curious behaviour of twin boys new to the senior school. She follows the twins to the headmaster's office, but they vanish into thin...