Sandokan explains his plan to his men. It is a rearguard offensive. At night, Yañez (still dressed up as a high ranking officer) makes good use of the arrival in the bay of a large number of small boats which are sending up signal flares to make the soldiers believe that a large fleet is approaching Mompracem. In this way, he makes all the garrison think that the island is being attacked, thus ensuring that all the troops will be concentrated in one place. The way is open for Sandokan. Sandokan crosses the island and attacks from the rear, causing total confusion among the enemy. Previous to this, using his disguise and ingenuity, Yañez had managed to free the captive pirates, who are now lying in wait for the moment when they will take part in the battle. A terrible battle ensues in which the help of the pirates is decisive. The enemy feels hemmed in and Yañez takes advantage of this to advise the major in charge of the garrison to surrender at once. Finally, Sandokan, Yañez and their men gain victory. Mompracem has been liberated.