The title itself is the novel’s central metaphor. Castel believes he is traveling through a lonely and dark tunnel , hermetically sealed off from the rest of society [14]. He briefly believes María Iribarne is a fellow traveler in a parallel tunnel who can truly understand him because she noticed a small, ignored detail in his painting Maternidad —a window looking out onto a lonely beach [2, 13].
Castel is an archetype of the alienated, paranoid man [18]. His misanthropy is profound; he views the world with contempt, especially art critics and society at large. His life is a series of extensive rationalizations and anxieties , as he over-analyzes every interaction to the point of absurdity [3, 14]. The Metaphor of the Tunnel El Tunel
However, Castel’s tragedy lies in his realization that their "tunnels" never truly merged. While he sought exclusive possession to end his isolation, María remained a separate, enigmatic entity [5]. This leads to his ultimate disappointment and the violent conclusion that his "tunnel" was always solitary. The Failure of Communication The title itself is the novel’s central metaphor