A Swiftly Tilting Planet (Time Quintet #3)
The Murry and OKeefe families enlist the help of the unicorn, Gaudior, to save the world from imminent nuclear war. In this companion volume to A Wrinkle In  Time (Newbery Award winner) and A Wind In The Door, fifteen-year-old  Charles Wallace and the unicorn Gaudior undertake a perilous journey through time in a desperate attempt to stop the destruction of the world by the  mad dictator Madog Branzillo. They are not alone in  their quest. Charles Wallace's sister, Meg -- grown and expecting her first child, but still able to enter her brother's thoughts and emotions by "kything" -- goes with him in spirit. But in overcoming the challenges, Charles Wallace must face the ultimate test of his faith and  will, as he is sent within four people from  another time, there to search for a way to avert the  tragedy threatening them all. - Publisher.
Science fiction, Juvenile fiction, Space and time in literature, Space and time, Good and evil
Madeleine L'Engle
American writer