Ariel, Miranda's clone, is becoming a person in her own right. Ariel is living with Miranda and they arebecoming close, as sisters do. Everything seems perfect, until Miranda starts noticing things that don't seem to fit with the Ariel she knows. She sees her sister in places she shouldn't be, doing things Ariel would never be doing, and Miranda begins to wonder if she herself is going crazy. But then Ariel beginsacting stranger than ever and Miranda gets a horrible feeling... what if there's more than one clone? And if so, can she find out what's going on and give Ariel back the life she's built before it's too late?

The thrilling sequel to Cloning Miranda and The Second Clone . When Miranda is accused of vandalism on school property, she's confident she can clear her name - until she's shown the security tapes. Even she can't tell that the girl on the tapes isn't her, or her cloned "twin" sister Ariel. Miranda must fight to clear her name or face being expelled, and possibly charged by the police. But one way or another, she knows she can't tell the truth to the authorities, or share her suspicions about the real culprit. Meanwhile, Dr. Mullen, her creator, has called a press conference to announce that he is the first scientist ever to create a living human clone. Could the girl on the security tape be yet another Mullen-made Miranda clone? Or could it be Eve, the dying third clone that Mullen kidnapped? No matter what, it looks like Miranda and Ariel are about to face the biggest challenge of their lives.