Besar, his pirates, Kim Kim, Flint, and the two other sailors from the Gerrymander set sail for Vishnu's island in Besar's pirate ship. Meanwhile, the crewmen of the Gerrymander escape and set Boll free. They take back control of the Gerrymander from the pirates and set out in the Gerrymander in pursuit of Besar. To keep Besar from losing them during a moonless night, Boll and two of his men ride ahead of the Gerrymander in a longboat and send signals back to the Gerrymander to allow her to remain on Besar's tail. While they are doing this, one of the Gerrymander's sailors aboard Besar's ship, Wilson, sneaks off the ship and swims to Boll after overhearing where Besar is heading. Wilson's information allows Boll and his crew to identify Vishnu's island as Krakatoa.