CHAPTER I
TWINS
CHAPTER II
PLANS GO ASTRAY
CHAPTER III
THE “SEAHAWK”
CHAPTER IV
THE YELLOW FLAG
CHAPTER V
HOW ADVENTURE CAME TO JOKER
CHAPTER VI
SEA-CAVES
CHAPTER VII
THE ISLAND
CHAPTER VIII
THEY MAKE A RAID
CHAPTER IX
VOYAGES OF DISCOVERY
CHAPTER X
STRANGE VOICES
CHAPTER XI
THE ENEMY IN SIGHT
CHAPTER XII
HOW DEREK PAID A DEBT
CHAPTER XIII
THE HIDDEN TRACK
CHAPTER XIV
AT THE BACK DOOR
CHAPTER XV
STRATEGY AND TACTICS
CHAPTER XVI
A BRUSH WITH THE ENEMY
CHAPTER XVII
BACK DOOR VISITORS
CHAPTER XVIII
TRACKED
CHAPTER XIX
PURSUIT
CHAPTER XX
DEREK TAKES PASSENGERS
CHAPTER XXI
THE LAW TAKES CHARGE
