What is wrinkle of time about?

First of all, it is called A Wrinkle In Time. It is about a little girl, Meg Murry, her brother, Charles Wallace Murry, and a new friend, Calvin O'Keefe. They go on an adventure with three old ladies to new planets, and land on a planet to rescue Meg and her brother's father. By the way, the two siblings have two other siblings who are twins, and a mom, Mrs. Murry, who is a doctor like their father.