Return to Isle of the Lost (Descendants #2) by Melissa de la Cruz

There's no place
like home..

Especially if home is the infamous
Isle of the Lost. Mal, Evie, Carlos and Jay
haven't exactly turned their villainous noses
up at the comforts of Auradon after spending
their childhoods banished on the Isle. After all,
meeting princes and starring on the Tourney
team aren't nearly as terrible as Mal and her
friends once thought they would be.

But when they receive a mysterious invitation
to return to the Isle, Mal, Evie, Carlos and
Jay can't help feeling comfortable in their old
hood -- and their old ways. Not everything
is how they left it, though, and when they
discover a dark mystery at the Isle's core,
they'll have to combine all of their talents
in order to save the kingdom.