A well written, fast paced book, but quite complex and for mature readers.
In the final book of the series, the Six come together as the Dark rises for the last time. But before the Dark can be banished, the final Thing of Power must be collected, and the Dark will stop at nothing to prevent that from happening.
The difference between the Light and Dark is once again clearly shown, with those of the Light being portrayed as good, while those working for the Dark are evil.
At the beginning of the book, there is a scene with a racist character named Mr. Moore who while pleasant at first, soon turns quite violent and Will sees this as a "channel through which the power of the Dark would take control of the Earth". However, the Stantons are presented as holding the opposite view to Mr Moore.
The Dark Ones are portrayed as quite willing to cheat (they prevent Merriman from helping Will and Bran by endangering the Drews) and when one of their agents fails in his mission it is suggested that they will go after his family in revenge.
Those on the side of the Light however, are portrayed as loyal. A character in the Lost Land is shown to have defied the traditions of his home in aiding the Light out of loyalty to his king. At the end Bran also shows loyalty despite having to sacrifice his birthright.
The characters also lie to adults in order to continue on their mission, but they don't seem to have a problem with this.
Once again it is suggested that the Light and the Dark are the powers that are controlling the universe, with no room for a higher power. At the very end of the book the characters set off to reach the "Tree of Life" and it is said that whoever controls the Tree has the right "to command the Old Magic and the Wild Magic, to drive all rival powers out of the world."
Magic both good and bad plays a large part in this story, but it is not overt and there are no spoken spells.
It is suggested that The Lady may be Juno, a Roman Goddess.
The major sticking point is that at the end Merriman tells the children that the World is now theirs and that they can't expect the "Second coming of anyone," which goes against the Christians' belief in the Second Coming of Jesus Christ.
Several monsters appear to frighten the children, and there is a mention of a battle against the English later in the book. However, most of the "battles" are more battles of wits than actual violence.
Drug and Alcohol Content
When trying to explain the Light and the Dark to Stephen, Will asks if he thinks "he [Will] is involved in drug running."
It is implied that Bran's mother committed adultery in the past.
Crude or Profane Language or Content
The racist Mr. Moore and his son refer to Indians, and one boy in particular, as "Pakkies" and "Wigs"; they also use the word "hell." Stephen, Will's brother, takes God's name in vain a couple times, as do the rest of the Stantons.
As the last in the series this book is excellent in tying up all the loose ends. However, it is unwise to read this book without at least a passable understanding of the others, as there is a lot of back referencing.
As a story it is much more grown-up than the others of the Dark is Rising Sequence, with the characters faced with a lot of moral decisions that could possibly decide the fate of the world, and it is implied that on both sides of Dark and Light there is no room for emotions - simply a desire to achieve their aims. I believe that younger children who have enjoyed the rest of Susan Cooper's work would be advised to leave this for a few years until they are more established in their faith, as it raises several awkward questions.