Primary human characters
Margaret "Meg" Murry
Meg is the outcast of the family and also the oldest child of scientists Alex and Kate Murry. Mathematically brilliant but less than adept at other subjects in school, Meg is "awkward", unpopular, and defensive around authority figures as well as her peers. Although she has the brains to accomplish difficult tasks, she rarely puts her strengths to use. She adores her mother and three brothers especially her youngest brother, Charles Wallace, and weeps much for her missing father. Like many adolescent girls, Meg is unhappy with her physical appearance, particularly her mouse-brown, unruly hair, braces and glasses, and considers herself a "monster" in comparison with her mother. But then she meets Calvin, a boy she falls in love with. She is about thirteen years old, and is a couple of grades below Calvin, who is fourteen years old but in eleventh grade. Introduced on the first page of the book, she is the story's main protagonist.
Charles Wallace Murry
Charles Wallace is the youngest Murry child. He is very smart and is the most extraordinary and the most vulnerable of the novel's human characters, and the youngest to journey to Camazotz. Charles Wallace did not talk at all until he was nearly four years old, at which time he began to speak in complete sentences. Now five years old, Charles Wallace speaks only to his family, but can empathically or telepathically "read" certain people's thoughts and feelings, and above that has an extraordinary vocabulary. A biological "sport," he is intellectually curious, loving, and unfazed by extraordinary people and events. He was the first to meet the Mrs W's and brought Meg to see them. Initially able to block IT out of his mind, he opens his mind to the Man with Red Eyes and thus falls under IT's control.
Calvin is the third oldest of Paddy and Branwen O'Keefe's eleven children, a tall, thin, red-haired 14-year-old high school junior who is not the best in math but has to study to play on the school basketball team, and is one of the popular boys in high school. His mother is a very cranky, tired woman with too many children. Neglected by his own family, Calvin joyfully enters the lives of the Murry family, starting in Chapter Two. He also loves Meg Murry. He shows some signs of being able to communicate telepathically, the same power Charles Wallace seems to have, a technique referred to in later books as kything. He also feels as if he has been hiding his true self all his life, and likes the Murry family much more than his own, which is characterized by abuse and dysfunctional dynamics. Calvin also supported Meg through the adventure.
Primary immortal characters
The three characters of Mrs Whatsit, Mrs Who, and Mrs Which are angelic beings who have the ability to travel at will across large stretches of time and space by dematerializing and rematerializing. They do not have a fixed physical form, but appear to humans as elderly women. However, they are capable of metamorphosing into other creatures. All of them are billions of years old. Mrs Whatsit, in particular, was engaged in war with the Darkness.
Mrs Whatsit is first described as a very old woman wrapped in layers of clothes and first appears in chapter one. Charles Wallace, a five-year-old boy in the book, found her in a 'haunted house' in the woods, where she has been living with her two friends, Mrs Who and Mrs Which. Mrs Whatsit is the youngest of the Mrs 'W's (despite being over 2 billion years old), and the best of the three at interacting with the children.
In Chapter Four, the group (Charles Wallace, Calvin, and Meg) witnesses the physical transformation of Mrs Whatsit into a centaur-like winged being on the planet Uriel. Mrs Whatsit is also revealed to have been a star that sacrificed itself by exploding in order to destroy a section of the Black Thing.
Mrs Who is described as a plump woman with spectacles. She communicates in Latin, Spanish, Italian, German, French, Portuguese and Greek, notably quoting William Shakespeare, Pascal, Dante, Seneca, A. Perez, Horace, Cervantes, Delille, Euripides, the Bible and Goethe. Mrs Whatsit explains that Mrs Who finds it "difficult to verbalize" in her own words.
Mrs. Which's physical appearance is not set; she appears as a shimmering light most of the time. However, she does once take on the appearance of a traditional witch, complete with black hat and broom. She does not stay long in this form, though, as corporeal appearance is quite difficult for her to maintain. She first appears at the end of Chapter 3. She is the wisest of, and the clear leader of the three women, and upon appearing, immediately demonstrates her vast knowledge of understanding in tesseract travel. Her distinguishing quirk is her long, drawn-out method of speech, symbolized by doubled and tripled consonants in her words (as in; "Nnoww, cchilldrenn, yyou musstt nott bee frrightennedd att whatt iss ggoingg tto hhappenn,"). She is the one who usually provides the group, most especially Meg, with the clues the children need to solve the problems encountered during their travels.
The Man with Red Eyes
The Man with Red Eyes is a being whom Meg, Charles Wallace, and Calvin encounter on their quest to rescue Meg and Charles Wallace's father on the planet Camazotz. He is the Prime Coordinator on that planet. Although he appears human, he explains that IT actually talks through him, like a robot or demented puppet; that he is a part of IT. He entices Charles Wallace to look into his glowing red eyes in order to find his father. When Charles Wallace does so, he too becomes possessed by the mind of IT, after which the Man with Red Eyes drops out of the story. Then, the man with red eyes tries to capture Meg, Calvin, and Charles Wallace.
IT is the bodiless telepathic brain that dominates the planet of Camazotz. IT controls all the people in Camazotz and makes people often do same things together in a mechanistic synchronicity as if they were robots. IT speaks through The Man With Red Eyes and later through Charles Wallace, and is functionally part of the interstellar cloud of evil called the Black Thing. IT is described as slightly larger than a human brain. Housed in a dome near the "CENTRAL Central Intelligence" building, IT is said to pulse and quiver on ITs dais. ITs aim is to enforce absolute conformity on Camazotz, with the claimed benefit of eliminating war, unhappiness and inefficiency. However, IT is aware of cruelty, referring to "ITself" as "the Happiest Sadist". While IT usually speaks through one of ITs pawns, IT can speak directly to people through telepathy, but IT only does this once throughout the entire novel. ITs name is always used whenever IT is spoken of (rather than the pronoun "it"), so pervasively that even the word "itself" is rewritten as "ITself."
The Black Thing
The Black Thing is pure evil. It is the Black Thing that Mr. Murry is fighting. The Black Thing and IT are very similar. The Black Thing has been fought by many people who have added to the world peace. According to The Mrs W's the Black Thing is the source of all evil in the universe. Also, Mrs. Whatsit was a star once then the black thing took over. so she repulsed and stopped the black thing for a while.
Secondary human characters
Dr. Alex Murry
Meg's father is a physicist, researching the mysteries of the space/time continuum, specifically five-dimensional means of travel between planets. He is also the father of Meg, Sandy, Dennys and Charles Wallace. He has been missing for some time as the novel opens. Not even his government colleagues know where he is. He is usually referred to as Mr. Murry. His first name is revealed in the fifth and last Time novel An Acceptable Time. In the television adaptation of A Wrinkle in Time, he is renamed Jack. He first appears in a flashback in Chapter One.
Dr. Kate Murry
Meg's mother is a microbiologist, wife of Dr. Alexander Murry, and mother of the four Murry children. She is considered beautiful by the Murry children and others, having "flaming red hair" and violet eyes. Her physical attractiveness, academic and scientific accomplishments give Meg a bit of an inferiority complex. She is introduced in Chapter One, and usually referred to as Mrs. Murry. As in her husband's case, her first name is given in the subsequently published An Acceptable Time. The television version of her character is renamed Dana.
Sandy and his twin brother Dennys are the middle children in the Murry family, older than Charles Wallace but younger than Meg. They are 10 years old at the time of this book. Sandy is named after his father, Dr. Alex Murry. Although they are certainly intelligent, Sandy and his twin are considered the "normal" children in the family: B students, good at sports, and well able to fit in with their peers. Of the twins, Sandy is generally the leader, and the more pragmatic of the two. He and Dennys first appear in Chapter One.
Dennys is the twin of Sandy Murry. Dennys and his twin are usually inseparable, with Dennys generally following Sandy's lead. However, Dennys is slightly less skeptical than his brother about the strange theories and even stranger adventures of Meg and Charles Wallace. (Note: The name Dennys is a shortened version of "Dionysus", which is the name of a Greek god, but is pronounced the same way as the more common spelling "Dennis.")
Mrs. Buncombe - The wife of the constable in Meg's hometown, who has twelve bed-sheets stolen from her at the beginning of the novel.
Mr. Jenkins - Meg's cold and unfeeling high-school principal who calls her "belligerent and uncooperative" and implies that her family is in denial about Mr. Murry's true whereabouts.
Supporting immortal characters
The Happy Medium lives in a cavern on a planet in Orion's Belt. Human in appearance, she is described as wearing a satin gown and a silk turban, and uses a crystal ball to look at distant places and people. Her title comes from the character's jolly temperament, and her preference for looking at happy things. She helps Meg, Calvin, and Charles Wallace see The Black Thing through the crystal ball and understand what they are fighting against. She is introduced in chapter five. (The name "Happy Medium" is a pun alluding to the common expression for reaching an acceptable compromise: "to find a happy medium.")
Aunt Beast is a character who takes care of Meg on the planet Ixchel after Meg is "frozen" by the Black Thing. Introduced in chapter ten, the character has four arms, no eyes, and numerous long, waving tentacles instead of fingers. Tall, gray in color, sightless and telepathic, Aunt Beast has a motherly, nurturing attitude toward Meg. The name Aunt Beast is one that Meg and the alien come up with together, based on the character's perusal of Meg's mind. The character's actual name, if any, is not given.