L'Engle's book, an exciting science fantasy story, is about a young girl named Meg who travels through space to find her father, a scientist who has gone missing. Three celestial beings named Mrs. Whatsit, Mrs. Who, and Mrs. Which help Meg on her quest, which develops into a battle between good and evil. In the book, these beings guide Meg with scriptures like 1 Corinthians 1:27–29 and John 1:5.
Another unmistakable Christian element in the book is when Meg's brother, Charles, realizes that Jesus is a "fighter of evil", and even asks Meg's friend Calvin to read him a bedtime story from Genesis.
These and other details will not be a part of Disney's epic adaptation. Lee said she focused instead on the battle between light and darkness, which is "universal" and not exclusively Christian:
"In a sad way, some of the other elements are more important right now and bigger — sort of this fight of light against darkness. It's a universal thing and timeless and seems to be a battle that has to keep being had."
"I can't put words in [Madeleine L'Engle's] mouth — and I worked with one of our producers, Catherine Hand, who was very close to her — but that wasn't her intention," Lee added, arguing that including Bible verses and other Christian elements would stray from the inclusiveness and diversity Disney strives for. "Her intention was looking at the ordinary real hero in an extraordinary situation...The power of love in this world, and we stayed very true to that. And her lens through it was Christianity and everyone has a different lens in."
In an interview with America Magazine, a Jesuit publication, Jim Whitaker, another of the film's producers and a lay Catholic, defended that the film still retains strong themes of faith:
"I think the movie has many faith elements in it. It's truly a journey of a girl who, without seeing and having real evidence of her father, makes a bargain to travel throughout the universe to find him...And I think that's a really powerful metaphor and statement that's worth considering about the nature of faith. How you have faith, without being able to have 'real' evidence, is kind of the key, and challenge, of life."