Of course. Here is a detailed description of the book *A Wind in the Door* by Madeleine L'Engle, based on the information you provided.
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### **Book Description: A Wind in the Door**
This is a description of the second book in Madeleine L'Engle's famous *Time Quintet* series.
**Bibliographic Information**
* **Titel (Title):** *A Wind in the Door*
* **Autorin (Author):** Madeleine L'Engle
* **Verlag (Publisher):** Farrar, Straus and Giroux (often abbreviated as FSG)
* **ISBN:** 978-0-312-36754-0 (This ISBN corresponds to a paperback edition from Square Fish, an imprint of Macmillan/Farrar, Straus and Giroux).
* **Reihe (Series):** Book 2 of the *Time Quintet*
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### **Plot Summary (Handlung)**
The story continues the adventures of the Murry family, focusing again on Meg Murry and her gifted younger brother, Charles Wallace.
A year after the events of *A Wrinkle in Time*, Charles Wallace has started school but is having trouble fitting in. He soon falls gravely ill with a mysterious disease that is affecting his mitochondria--the energy-producing parts of his cells.
One afternoon, in their garden, Meg, Charles Wallace, and their friend Calvin O'Keefe encounter a new, otherworldly being: a "cherubim" named Proginoskes. Proginoskes is a creature of immense size with countless wings and eyes, who has come to help them. He explains that the universe is threatened by the Echthroi, evil beings who seek to "un-name" things and spread nothingness (or "X"). The Echthroi are attacking Charles Wallace on a microscopic level, trying to destroy his farandolae (fictional organelles within mitochondria) and extinguish his life.
To save Charles Wallace, Meg, Calvin, and the reluctant school principal, Mr. Jenkins, must journey *inside* Charles Wallace's body. They are made small enough to enter one of his mitochondria and must help the farandolae fight off the Echthroi. The journey is a profound test for Meg, who must learn to love and connect with Mr. Jenkins, a person she deeply dislikes, in order to succeed. The adventure explores the idea that the battles fought in the smallest, microscopic spaces are just as important as the battles fought across the galaxies.
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### **Themes and Concepts (Themen und Konzepte)**
* **The Macrocosm and Microcosm:** While the first book explored the vastness of space, this book explores the infinite complexity of the microscopic world, suggesting that the universe is equally grand at every scale.
* **Love and Sacrifice:** The central theme is the power of selfless love. Meg's ability to love someone she finds unlovable is key to defeating the Echthroi. The concept of self-sacrifice is also crucial to the story's climax.
* **The Power of Naming:** The act of "naming"--of knowing and accepting something or someone for what they truly are--is presented as a creative and powerful force against the chaos and destruction of the Echthroi.
* **Science and Spirituality:** As with her other works, L'Engle masterfully blends concepts from quantum physics, biology, and Christian theology to create a unique and thought-provoking narrative.
* **Interconnectedness:** The book emphasizes that everything in the universe, from a star to a single cell's mitochondrion, is connected and interdependent.
In summary, *A Wind in the Door* is a deep and imaginative sequel that moves the action from outer space to "inner space," presenting a challenging and philosophical adventure about the nature of life, love, and existenc