Regina's Song is a murder mystery novel by David and Leigh Eddings that takes place in Seattle, Washington. Twins Regina and Renata are so identical that even their mother can’t tell them apart. Eerily attuned to one another, they often speak together in a secret language no one else can understand. Then tragedy strikes when one of the twins is viciously murdered. The remaining twin is so traumatized, she reverts to the cryptic language she once shared with her sister. What’s more, since identical twins share identical DNA, there is no way to tell which girl was the victim. The parents believe the surviving twin is Renata and have no choice but to commit her to an institution. There she lives, incomprehensible to the rest of the world. Until the day Mark, a family friend, comes to visit a