Rachel and alice are an extremely rare kind of identical twins-so identical that even their aunt and uncle, whom they've lived with since their parents passed away, can't tell them apart. But the sisters are connected in...Rachel and alice are an extremely rare kind of identical twins-so identical that even their aunt and uncle, whom they've lived with since their parents passed away, can't tell them apart. But the sisters are connected in a way that goes well beyond their surfaces: when one experiences pain, the other exhibits the exact same signs of distress.