One very unique aspect that I loved about this story is that you don't find out the solution to the mystery until (literally) the last pages! I would never have guessed! It was so interesting and I really liked how things turned out.
Being a lover of nautical things myself, I really enjoyed the major sections of this book that took place on board the different ships, and one of my favorite characters was Winters- the gruff old sailor. (I REALLY liked his follow-up at the end. :))
I was happily surprised by this book- most novels that are a bit older and are nearly 400 pages seem to start dragging by the end (at least in my opinion); but Prisoners of the Sea didn't have a boring sentence between the front and back covers!
I would (and will) highly recommend this book to everyone!