Vampirates, tome 5
Justin Somper2011

« Determined to stake their claim on the dark waters, renegade Vampirates are expanding. But the Pirate Federation and the once-neutral Nocturnal Vampirates are determined to thwart their efforts and destroy every rebel Vampirate ship in sight. Meanwhile, shocking secrets about their family history have twins Connor and Grace questioning every allegiance they've ever made. There's a bloody battle brewing on the seas, and one thing is tragically clear: This time, no ship is safe. » (Source : amazon.com)

Titre original : Vampirates, book 5: Empire of Night (2011)