The Neptune Revenge

As Nere and here friends, old and new return from the hectic Atlantea, they don't know what hard, harsh times are ahead of them. Even if everything seems perfect, Nere and her brother James notice change in climate.
A few months ago, a group of Neptune kids were sent to retrieve two of their own, and an invention that can save the world due to climate change. When they embark on another dangerous journey, an old 'friend' shows up to seek their revenge.
And even worse, Nere's dad and the rest of the staff at Safety Harbor make a dangerous decision that will put The Project and all The Neptune Kids in danger.