This is the sixth and final book in the Pegasus series, which follows the adventures of Emily, a mortal girl from New York who one day discovers a wounded Pegasus on her rooftop. In the previous book, Emily and her friends went to Hawaii and later Emily and the Xan Riza who lived inside of her were separated into two different bodies. Lorin, the Titan who also inherited part of Riza’s Xan powers returned to Olympus with them and Emily must teach her how to control her powers with compassion. Emily struggles with her new, less-powerful body and trains with Diana to strengthen it. Emily discovers that her human friends were caught by the secret agency CRU (Central Research Unit) and are suffering. Agent B, who helped save Olympus in the fourth book, and whose real name was Benedict Richard Williams and the Greek girl, Stella Giannakou. Also captured is Earl from the first book and Franke, the boy who helped the group in Las Vegas. 

Emily decides to head off to England and save them; Cupid proposes to go with her and Pegasus. Tom then sends Paelen and Joel to help her as well, since they are a team and should continue working together. Vulcan also joins the group and then Lorin. Emily, Cupid and Pegasus are captured by the CRU and since they do not recognize Emily (with her new features), Cupid pretends that she is his wife, Psyche. In their prison, they meet the menacing shadow Titans who were created after Emily used her powers last time to vanquish Saturn. The CRU feed these new horrible creatures, the clones they have created from the Olympians’ blood, but tell Emily it was her power that created them. These shadow Titans torment Vulcan, Joel Paelen and Lorin as well, when they reveal their innermost fears and insecurities. Then the shadow Titans agree to replace the group with Lorin alone, and she agrees, in order to save Paelen. The freed Titans then rampage over London and the group reunites with Emily on Xanadu. In the end Emily and Riza transport the Olympians to Xanadu and she sacrifices herself and lets the solar stream destroy Olympus with the shadow Titans. In the last chapter Emily must choose whether she wishes to live ordinary life on earth, or be a Xan and return to her friends. Emily chooses the life of the Xan, implying that her adventures will probably continue.

This book carries an ominous title that signifies not only a possible end of Olympus but also of the series; this is where everything comes to a conclusion. This also correlates with Emily’s own sense that everything is ending, due to the massive changes that happened in the last war against the Titans. As with the other books, Emily faces another physical and mental challenge she must overcome; this time her Olympian body changes following her separation from Riza. Emily feels lonely and insecure, as if her friends were avoiding her. While some of them are busy with their own lives, Joel cannot resolve his own feelings towards her and keep his distance from her. The powers, of which she was once so afraid, are gone now and she misses them. She still feels incomplete. Her sole comfort is loyal Pegasus. Pegasus represents the power of hope, dreams, of bettering yourself and overcoming challenges. He is Emily’s real source of strength. This could also be since Pegasus is a stallion, and therefore does not undergo the changes that humans (and gods) do; he does not fall in love or have a change of heart. 

Emily resents her new body, and its perfection. She does not feel like herself anymore. This could relate to puberty and the physical changes which adolescents go through, until they get used to their appearance and get comfortable in their own skin. The author makes Emily go through various stages of puberty, which are intensified due to the fantasy element of the story. Therefore Emily’s insecurities and troubles are both very easy to relate to on the one hand, but also at the same time magnified. As Emily notes, if she cannot accept herself, how could others? The author is emphasizing the importance of inner beauty beyond external beauty. Agent Tom, who was turned into a Sphinx by Emily, also stresses this point to her. This is a didactic lesson, which the author conveys via Emily’s mysterious transformation. Emily quite literally loses her old self, yet it just the external shell which was lost, not her true essence.

While Emily regrets losing Riza, her anger at Lorin grows. Both Riza and Lorin were part of Emily and similar to, yet different from, her. Emily must learn to accept them both in order to mature as a person. She resents the relationship between Lorin and Paelen and is sad because Joel avoids her. This is where the adults enter the scene. Tom and her father talk to her and encourage her. It is important for the author to show that Emily does not suppress her feelings (even though she tries to do so) and that the adults in her life (especially the father-figures) are attentive to her and talk to her about her emotions. It is interesting that it was Cupid who first accompanied Emily in her mission to London. Cupid was a coward at first but has matured and he wishes to save his human friends as well. From a metaphorical point of view, Emily, who struggles with her own emotions and self-esteem, is going on a self-discovery voyage accompanied by none other than the personification of Love. The companionship of Cupid is therefore crucial, not only for the success of the rescue mission, but also for the element of love which enables Emily to save herself. Going to London without Riza means that Emily will need to have faith in her remaining powers and in her abilities. We do not know how old Emily is; in the first book she was 13 and time has certainly passed since then, but she became ageless when she was on Olympus.  However, this deliberate uncertainty makes her relatable to the readers who can be of different ages. She is going through similar difficulties as the readers themselves, which enables them to identify with her.

The author devotes a chapter to a conversation between Paelen and Joel, who also regret their behavior towards Emily. It is important that she gives all different viewpoints allowing her readers to understand that sometime people hurt each other without intending to do so. Paelen and Joel care greatly for Emily yet they also struggle with their own emotions, like she does. Giving them an opportunity to show their own concerns demonstrates to the readers that if people are too self-absorbed, they might not notice others’ feelings. Emily thinks her friends have deserted her and she does not know how much they regret their actions, because of the lack of communication between them. Talking openly is the key to work things out.

The shadow Titans are the main villains of this story. They act as male and female voices, who represent the innermost fears of the characters, revealing hidden truths and pains. They act, it seems, as the little voice inside of each of us, which tells us how unworthy we are and how useless. Vanquishing them means that our good inner voice, our self-belief, can overcome these fears, these little whispering demons of our minds.

In the end, Emily finds her true purpose in life through rescuing people and becoming a full Xan. This becomes her main concern and she lets go of her former anxieties and doubts. This could be equivalent to a decision one comes to regarding plans for the future. Finding purpose is crucial for finding your path in life; it may be a small or big aim, as long as it gives you direction and meaning. Emily understands that actions carry consequences, as when she used her powers against the Titans in the past and thus created the shadow Titans. Taking responsibility for one’s actions as well as one’s mistakes, is a sign of adulthood. The older Xan, Riza’s father, admits to Emily that he gave her all of his powers and she could choose whether to become a full Xan and help Riza protect the universe. He tells her that the powers are locked behind psychic doors which she must break if she is ready for this kind of responsibility (these powers are available when she uses them to protect others). We could again interpret this as a metaphor for the powers hidden in us, in our mind and soul, and of which we must be aware in order to use them. Furthermore, since, in order for Emily to unlock the last door, she must call her late mother’s name, a cycle or a closure of some sort is presented.  Emily is growing and changing, yet she does not forget who she was, and her parents, in the form of her mother, give her that strength; thus she can cope with the loss of her mother and the changes she is about to go through. This presents a message about dealing with loss and how our beloved are always with us, protecting us and being part of us, even if we cannot see them anymore.

Like the other books in the series, this volume has an environmental message, in that Riza saves an entire planet facing a supernova by relocating the inhabitants to a new place. This is a message of hope, even if the danger seems imminent. The author would like us to treat nature and living creatures with respect. As long as people work together there is hope. In this story, Olympians, humans - including even CRU agents -, even Saturn, work together to save their earth from the Titans.