Answer:
There are many books in which I could pull from, but the best example would be The Hobbit by J.R.R Tolkien. Tolkien throws the reader into a mystical world set in Middle Earth. We are introduced with a Hobbit, who enjoys a quaint simple life.About half average human height, Tolkien presented hobbits as a variety of humanity, or close relatives thereof.
The Hobbit is selected by the wizard Gandalf to help Thorin and his party of Dwarves to reclaim their ancestral home and treasure, which has been taken over by the dragon Smaug. Bilbo sets out in The Hobbit timid and comfort-loving, and through his adventures grows to become a useful asset. Like many Hobbits, Bilbo Baggins does not like adventures, as it is not in their "nature." But Gandalf comes by to prove otherwise.
During the novel, Bilbo is recruited by Gandalf to help a pack of Dwarves reclaim their lost home. When Bilbo accepted this journey, we are already seeing Bilbo's true colors coming through. This also allows you to use the lens quotation because it is revealing who the character truly is even when people are not watching. Bilbo scurries along to meet the rest of his party as the entirety of Bag End shuns him. A great example of Bilbo's character in the dark is when he is literally in the dark. His quick thoughts are what saves him from being Gollum's next meal when he falls into his cave.
Bilbo saved his own life that day because of his witty puzzles and quick actions against Gollum. Bilbo fought as hard as he possibly could to achieve his goal, and he never gave up. At heart, Bilbo is an adventurer, just like the rest of the Took side of his family. With the help of a couple of new friends, Bilbo was able to show his "true character in the dark" to the world. In addition to this Bilbo got to discover who he really is and learn how to overcome new challeneges.
As a result from all the challenges Bilbo encountered he showed his true color. To put it into other words, the readers discovered who he was even when he did not believe it himself. This Novel put excellent use to the lens quotation because it allows you to open your mind to how it suits other texts and situations.
Explanation: I know this is late im really sorry, still hope it works :) This is made for a five paragraph format but you might want to make some alterations. The essay is based off the novel 'The Hobbit'
Hope it helps regardless <3