The Moroi radicals are a group of Moroi who oppose Lissa Dragomir as queen. They try and get her removed from the throne by killing her illegitimate sister, Jillian. If Lissa does not have another family member, she is not allowed to be queen due to the quorum law. The radicals sent a group of assains to kill Jill during a dinner party. The guardians assumed they were going for Lissa, so they neglected to protect Jill. They managed to kill her, even though Eddie realized what was happening and tried to help. Jill was brought back to life by Adrian Ivashkov using his Spirit powers, resulting in Jill being shadow-kissed.
Due to the attack (which took place between Last Sacrifice and Bloodlines), Jill, Eddie, and Sydney Sage travel to Palm Springs, California, to attend Amberwood Prep in order to hide Jill until Lissa can reverse the quorum law.