The Collector begins with recollection, as the narrator, Frederick Clegg, recounts his working-class childhood and young adulthood. He describes the feeling of inadequacy that invaded so much of his life and the worry that he is somehow lesser because he did not have a prestigious education or material wealth. When Frederick comes into possession of a large amount of money, he believes things will improve. However, Frederick soon realizes that money does not buy the respect of his peers. The elite upper class he once revered still does not view him as their equal; Frederick—and his aunt and cousin in particular—still bear the mark of their working-class origins. They do not speak or act like those in the upper class expect. They snub Frederick in restaurants, speak over him in conversations, and reject his attempts to integrate into their elitist culture.

In short: Frederick learns that money cannot bridge the social gap between those born into money and those who must earn it. His resentment does not lessen, so he begins to take his anger out on Miranda, as she represents the world he longs to occupy. In part, his envy aids his monstrous transformation throughout the novel. Although he does not embody the upper class's social status, Frederick carries its economic sway. As he explains early on, "Power corrupts, a teacher I had always said. And Money is Power." His financial status provides an unprecedented opportunity to act without inhibition; he can do whatever he wants because he has no limitations. Frederick’s newfound wealth compensates for his limited social status, and the potential of his newly discovered influence leads him to kidnap and mistreat Miranda. In one respect, Fowles criticizes the strict divisions that economic class has wrought on the social dynamic in twentieth-century Britain; however, he also cautions against allowing oneself to be ruled by money, as it is equally corrupting and freeing. 

Frederick calls his feelings for Miranda love. He imagines them living happily together, sleeping side by side, and waking up to the morning rain. In his mind, she adores his butterfly collection and compliments his skillful mounting and arranging. Frederick's vision of love has few roots in reality. Instead, the foundation of his love for Miranda is dreamlike delusion; he loves her for the traits he imagined her to have and the life he thought they might share. Calling his feelings love is a misnomer that degrades the word. Instead, what he feels is relentless obsession and repressed desire. Miranda embodies everything he wishes for: wealth and the social poise, education, and self-confidence that it conjures. 

Moreover, her physical appearance conjures a wealth of confusing feelings and desires. Miranda does not wear make-up, dress provocatively, act in a “la-di-da” manner, or overly sexualize herself. In Frederick’s mind, she is a paragon of female virtue; she is young and unmarred by the tokens of modern femininity upon which Frederick looks down. He sees Miranda paternally; in some ways, she is little more than a child to be protected, cared for, and loved. When she attempts to seduce him, he is disgusted. However, he soon learns that his disgust is not at her form but at her attempts to eroticize herself; when he views her nude body while she lies unconscious, he feels the desires he has suppressed. He sees her prone body as sexual, viewing her helpless form with the lust he had not yet felt. Indeed, Frederick’s view of love is simply one of control and acquiescence, seeking a woman he can mold to suit his every whim. At once, he...

The Collector has faced criticism for its often black-and-white message. Fowles takes up such controversial themes as economic class and its sociocultural consequences, the relationship between genders, and the expected nature of violence. In all these questions, there is a clear-cut dialectic of both good and evil, a clear good guy and bad guy in the sometimes-literal and sometimes-figurative captor/captive dynamic. However, Fowles’s focus on the question of fantasy and imagination is not nearly so clear; in some cases, it is a respite from the harsh truths of lived reality. In others, it serves to validate harmful delusions. Regardless of its consequences, Fowles writes of the universal yearning for the unreal, the allure of the life we wish to live. For both Frederick—who must face the derision of the woman he imagines himself loving—and Miranda—who seeks to transcend the four walls of the cellar in which she is imprisoned—fantasy is a welcome respite from life’s cruelty. Fowles does not condemn this escapism as folly. Instead, he welcomes it as a shared truth and attempts to convey how individual fantasies intersect and bleed into real life, asking where exactly the truth lies and not expecting an answer. 

One of the critical elements of The Collector is Miranda's development. As a twenty-one-year-old student from a wealthy background, her perspective is limited by her privilege, a fact that Frederick resents. However, her diary entries reveal the keen insight and curious gaze with which she views and evaluates the world. Although she often reprises the petulant trappings of her childhood—demanding luxury goods and rejecting Frederick’s negative view of the upper class—she is also contemplative and open-minded. The central tragedy of the novel is the ephemeral nature of her development. No matter how hard she tries, her confinement forces her into a state of stasis. In the chrysalis of the cellar, she evolves. Throughout the novel, Miranda blossoms into a mature adult with a more assured sense of self. However, her metamorphosis must forever remain incomplete, as she cannot burst forth from her isolation. Miranda remains trapped, caught eternally at the moment of transition.