The narrator is Robert Brown, tearaway son of a man who was rewarded by King William for his courage at the Battle of Boyne, and - because he disapproves of the breaking of the Limerick Treaty terms - holds land besides his own for a branch of the O’Neill’s. Robert is engaged in smuggling, more or less with the approval of the whole community. He is in love with the beautiful Rose Mary O’Neill, but has a playful friendship with Rebecca, the daughter of the Quaker from whom he borrows the boat in which he sails out to the French ship, on board which Col. Patrick O’Neill, in the service of the Emperor of Germany, on his way to the O’Neill’s on the Pretender’s business.
 Delivering Col. O’Neill to the ONeillsland, he discovers that his father has fended off an attack from Neeshy Hockon, the tory [highwayman] of the title. Robert rescues the Catholic fortune-teller (spae-wife) from the loyalist mob at Carrickfergus, and later meets her son Neesy Hockon. Col. O’Neill sets out to gather support for the Pretender, and is unhorsed and robbed by the tory of his money and his papers. He is found by Robert and brought to his father’s house. Robert is arrested for neglecting his duties as a militia man by the Colonel in Carrickfergus, and later acquitted at courtmartial.
 Charles O’Neill, who has gone to the bad, engages with Neeshy to have the stolen papers returned, and also to have Rebecca, whome he fancies, kidnapped. Meanwhile, Patrick O’Neill mets with the Protestant gentlement of Ulster seeking to enlist them for the King James; a messenger arrives from Dublin with news that the Scottish rebellion is over, and support crumbles. O’Neill retires to Brown’s house again. The Browns’ convinced that he is no danger to King George, agree to help him quit the country. Rebecca visits, and rebukes O’Neill for risking the Browns’ lives. Suddenly, the house is surrounded by the militia, searching. O’Neill prepares to fight, but Rebecca makes him take Robin’s soldier’s greatcoat to escape without detection.
 Charles rides to Carrickfergus and informs on Col. Patrick. John O’Neill and all the great Catholics are arrested, and Rose Mary goes to stay with the Quaker family. O’Neill hides in a quarry, where Rose Mary plans to meet her cousin for a last time. Rebecca and Rose Mary are both taken by Neeshy Hockon before they can reached him. Neeshy ties the girls up at his mother - the spaewife’s place, and explains his plan is to force Charles to marry Rebecca while he marries Rose Mary himself. He goes off for a bent priest. Brown and Col O’Neill have discovered their whereabouts by guesswork when Tam Lynn tell them that he’s seen Lesshy with two captive girls. They release them. Rose Mary plights her troth to Col. Patrick, and Brown inadvertantly spurns Rebecca.
 A sea-chase ensues, in which Brown eludes the English brig. On boad the Frenchman, Col. Patrick and Rose Mary are married. Rebecca goes abroad with them, spurned again by Robert who takes the view that she is safer in Germany than in Ireland, at the mercy of brigands like Neeshy Hockon. He now pledges himself to capture Neeshy. In the five-year epilogue of these events, the pursuit of Neeshy and his associates is told.
 Brown and the tory, now disguised as a redcoat, finally meet up in a Dundalk rally of the militia, where Brown is to leap horses in a contest with him. Hockon is recognised and captured after his victory in the contest, but not before Brown has cross swords with him. When Neeshy is hanged, he tells Brown where to find Col. O’Neill’s papers, in which the name of an important man is signed below an undertaking to support James III. Brown agrees with his father to go abroad to see Col. O’Neill on John O’Neill’s estate business.
 In London, he meets Rose Mary and Rebecca again; the Col. has now become Count Lichentstein. He is spotted by Charles O’Neill, and shortly after arrested for High Treason; Brown goes to the Lord whose signature is on the letter, and forces him to get an interview with Walpole for Brown.
 Sir Robert Walpole understands the case, and arranges Col Patrick’s release to the German ambassador. He offers Brown the commission of coast-officer after a grilling that confirms his secret information on his place in East Antrim society as leader of the smugglers. Brown appears not to understand the nature of the appointment in relating the events to Rebecca - whom he begs (‘my dear little comrade’) to return to Ireland for his sake. Not pleased with his appointment as a ‘preventive man,’ Brown begins to find in Rebecca’s response that ‘even a custom house officer may have his consolations.’