It is either coming out very late, or never. I just ordered it off Amazon.com. I think only books 1,2,and 3 came out in the US.
The first Skulduggery Pleasant book is just called 'Skulduggery Pleasant'. It was retitled "Skulduggery Pleasant: Scepter of the Ancients" for US release.
The Isthmus Curse was someone's imagination.The 4th Skulduggery Pleasant book, Dark Days, was released in the US on April 1, 2010.
It is the first book in the Skulduggery Pleasant series. It was called simply "Skulduggery Pleasant" in the US and in the UK. Many of the reviews of Skulduggery Pleasant have been copied over to this version of the book, including those on Amazon.
The third Skulduggery Pleasant novel, The Faceless Ones, was released in the US on August 25, 2009.
Only four of the Skulduggery books have been released so far, and they are (in order) : Skulduggery Pleasant Skulduggery Pleasant: Playing with Fire Skulduggery Pleasant: The Faceless Ones Skulduggery Pleasant: Dark Days If you live in the US, they are called: The Sceptre of the Ancients Playing with Fire The Faceless Ones The 5th book comes out in the UK on the 2nd of September 2010, and is probably going to be called Mortal Coil!
In the US, the book The Faceless Ones was released on August 25, 2009.
Book 4 hasn't been released yet so book 6 won't be out for a very long time. Derek said he was going to give the US another go, so hopefully for you, soon.
The 4th Skulduggery Pleasant novel, Dark Days, was released in the US on April 1, 2010.
There is already 5 out. Skulduggery Pleasant, Skulduggery Pleasant: Playing with Fire, Skulduggery Pleasant: The Faceless Ones, Skulduggery Pleasant: Dark Days and Skulduggery Pleasant: Mortal Coil. The 6th book is due out this month (September) and is called Skulduggery Pleasant: Death Bringer. After the 6th, there is going to be 3 more books. In conclusion: 9 books altogether I hope this helps :) Tanith Low
On Amazon
Book 4 of the Skulduggery Pleasant series is called "Dark Days".
The name of the 4th book was Dark Days (US release April 1, 2010).