The action ramps up considerably from the previous books and is pretty much relentless to the end. We meet another member of the nine living in India who has abilities such as teleporting and leaving just one member of the nine not yet revealed.
The book is extremely easy to read with short chapters and not much in the way of indepth description or even big words, the plot's not to complicated and can be a touch repetitive as the Lorien heroes constantly get trapped and escape, picking up various injury's along the way that are healed extremely quickly. We have the introduction of the Mogadorian leader who is ultimately more powerful than the Lorians and able to take there abilities from them but there is no back story to the evil aliens apart from the fact that they just want to conquer everything.
That said if the film series continues this would make an excellent addition with a good deal of action, multiple locations across the globe, a hint of romance, an emotional unexpected rescue, endless crashing helicopters and many dead Mogadorian's all from the power of the Lorian's.
In conclusion any negativity is aimed more at the genre, the book itself is high calibre action all the way and while not being excessively violent its definitely a rapid page turner with no respite, having read the first three books of the series there is enough interest there for me to continue and this would make an excellent film.