Spiral (Tunnels book 5) by Roderick Gordan and Brian Williams (I honestly don't know what to rate it.)

This whole series is a bit hit or miss.  There are incredibly boring parts that make you wonder why you're reading this at all, and then, there are amazing parts, like the end of this book, that make you wonder why you ever doubted it.  Basically, my idea of this book depends on when you ask me, and since it ended on an amazing part, I would just say this to anyone considering starting this series:  Stay with it until it gets to an interesting part.  It doesn't take all too long. 

Now, I'm going to assume that you've all read the previous books and not worry about spoilers from before this book.  *Spoiler Alert for the first four books* 

I'm just going to go ahead and tell you that this cover really doesn't work, in my opinion.  Sure, there's a Styx woman on the cover; but, what's up with the car and the hairy cave?  Please, please don't judge it on the cover.

I just realized how much stuff builds on itself.  This won't be the best summary, only because of spoilers. 

The Styx have pulled out all the stops.  The Phase is the next step.  It involves laying eggs to produce the warrior Styx.  In a mad dash to stop them, a number of things happen that complicate things.  From being trapped, to digging through places where there are loads of memories, to having a new girl introduced to make love interests more complicated.  A whole bunch of new characters are introduced and a couple of old favorites die. 

All in all, a pretty good book.  If you liked the earlier books, you will like this one.  I really loved the ending (if you don't count the epilogue).  And here's a random bit of info that will let you get a reference:  The Highfield Mole is another name for Tunnels, the first book in the series. 

There is, based on the ending, probably going to be another book in the series.  A bit too open to leave like that.

Anyway, I hope you all have a good summer.

P.S. Anyone who's read it, comment if you know/think why it's called "Spiral" because I'm really curious about that.