When ten-year-old Karen (Brooke Shields in her first screen appearance) is killed in church on the occasion of her first communion, her seemingly innocent older sister Alice (Paula Sheppard) becomes the prime suspect. Matters become complicated as more of Alice s family members are attacked, along with residents of her apartment building. Can a twelve-year-old girl be capable of such mayhem, or is someone else with a vicious plan destroying her family?