Return of the Skinny Guy

Summary:  A gang of jewel thieves has come to the riverbank, referred to by Detective Jeckerson as “the biggest gang of jewel thieves this world has ever known”.  Most of them are rounded up, but the mysterious boy Aquila - the boy with the eagle - and the strange little man known as Anato, the magician, manage to get away.  Aquila eventually helps them capture Anato, and in court it is revealed that a large stash of stolen jewels is hidden on Forgotten Island in the Caribbean.  In a storyline reminiscent of “Treasure Island”, the location of Forgotten Island is a secret known only to a few.  Anato makes a bargain to lead them there in exchange for his freedom and 20% of the value of the jewels.  Hawkins, Link, their fathers, Doc Waters, Jeckerson, and some police officers make the journey in three ships with Anato and some other crew members.  Once they reach the island, Anato and the crew members loyal to him make a grab for control of the whole situation.  Fighting breaks out, even including a battle in the bay between the three ships that includes a lot of gunfire and cannon fire.  It appears Anato is killed when he falls into a deep pit during a struggle with Jeckerson.  They good guys eventually prevail, and Hawkins and friends take the jewels back to the United States to be returned to their owners.  But some strange twists turn the story around at the end.