Guillermo del Toro has written and directed an epic that beautifully and tragically intertwines the stories of two dynamically different people in their search for immortality. It is not just a story about a little girl, Ofelia, escaping into her imagination to avoid the horrible world in which she finds herself. Nor is it simply about the resistance fighters in the woods taking down the brilliantly evil fascist, Captain Vidal. It is actually about these two characters, the innocent Ofelia and the wretched Captain Vidal, seeking immortality and the relationships they have within their family structure.
Captain Vidal seeks immortality in the way men have since we came down from the trees. He wants a male heir to carry on his family name. He is blinded by the singularity of this desire and has no interest in the daughter he has brought into his life by his marriage to the widow of his tailor. He is so single minded in his drive for a son that he is only too willing to allow his wife to die as long as his son can be saved
The Captain is the male ideal as monster. He is epitome of the wicked man. He is cold and calculating. He cares for no one, is excessively violent, and uses purely linear logic. As an antithesis to this portrayal of man, we are given Dr. Ferreiro, a caring man who is the healer in the truest sense. One gets the feeling that the doctor has no political motives and merely wishes to help those who need help. In the two of them we see the generic view of the male ideal as pure machismo and the ideal of the intellectual man.
The obvious symbol of Captain Vidal's quest for immortality is the watch he carries. His father's watch, he received after his father had died in battle. His father had smashed the watch so that the son would know the time of his death and know how "a brave man dies". The Captain repaired the watch and we see him meticulously maintaining it. As we find out at the end of the film, he intended to pass the watch on to his son at the time of his death in much the same way his father had sent the watch to him. Though he has achieved the son he sought he is denied his immortality by Mercedes and the resistance when they tell him that his son will never even know his name.
Ofelia's search for immortality is more subtle and complicated in its reasoning. She does not seek a way of people knowing her name for years to come, nor is her search a fearful wish to never die. Ofelia's dream is to live forever in the happiness she remembers before her father's death when she had a father and a mother that truly loved her. Her quest takes the form of a fairy tale as many childhood dreams do, although hers is much more frightening and dark for obvious reasons. Ironically, this is a fairy tale with a wicked stepfather instead of the archetypal wicked stepmother. While Captain Vidal cared for nothing but his immortality, on two occasions we see that Ofelia is willing to give up her quest for others. First when she delays her second task until her mother is feeling better and then when she is willing to give it all up rather than let the Faun spill her baby brother's blood to open the gate.
Ofelia's mother, Carmen, has been defeated by time and sorrow. She is so desperate for love that she will cling to even a monster like the Captain. She obviously cares for Ofelia but is so wrapped in the cloak of her own misery that she cannot see how terrible a world she has dragged her daughter into. The counterpoint to the frail woman by every measure is the maid, Mercedes. She works for the Captain so that she can bring intelligence and steal supplies for the rebels led by her brother. Even when she is captured she is able to bring about her own escape. In many ways, Mercedes takes the place of Ofelia's mother even while she is still alive and definitely once her mother dies. Here we see the wilting flower of a woman reliant on men for her happiness and livelihood set against the strong, independent woman who can take care of herself as well as the men around her.
There are three symbols of Ofelia's quest, the golden key, the dagger and her baby brother. These are the three items she is required to bring to the faun to prove that she is truly Princess Moanna, the immortal princess of the underworld and has not become a mortal. The golden key, I believe, represents simply the quest, the dagger represents the death in her past and the infant represents the childhood to which she wishes to return.
Ironically, in the end, the person that ensures that Ofelia gets her happy ending to the fairy tale is Captain Vidal. In spilling her innocent blood and opening the gate he completes the story that he began by bringing her and her mother out to the middle of the nowhere so that his son would be born where his father was. Thanks to the Captain Ofelia becomes Princess Moanna, Standing before her mother, the queen, and father, the king, and being applauded by the denizens of the underworld. Ofelia achieves her immortality through her death and Captain Vidal is denied his immortality through his.