Roderick Gordon & Brian Williams 
Terminal [EPUB ebook] 

In this sixth and concluding book of the Tunnels series, the Styx and their cohorts of deadly Armagi have swept across England, leaving death and devastation in their wake. It seems nothing can stop them now. Only a miracle can save the day and, in the inner world at the centre of the earth, Will and Elliott might just have stumbled upon one as they uncover ancient secrets that are fundamental to all human and Styx life.