As the curtain rises we see the pirates on their home ground, the rocky Cornish coast, celebrating with song and drink (1) the coming-of-age of Frederic who, at noon that very, will finish his apprenticeship and become a full-fledged pirate. To his comrades’ general consternation, however, Frederic announces that once his indentures are up he intends to leave them and devote himself to their extermination, explaining that although he loves them personally, he detests their profession. What’s more he states that his presence among them is in any case the result of an error. The pirates are baffled by this and Frederic calls upon Ruth, the only female among them, to explain. Ruth reveals (2) that years earlier when she was little Frederic’s nursemaid, the lad’s father had assigned her the task of apprenticing him to a ship’s pilot. Unfortunately, Ruth’s hearing was defective and she delivered the youngster into the hands of a pirate instead. Begging Frederic’s pardon and pledging him her love, she pleads that “the words were so much alike”. Frederic agrees, pointing out that, indeed, “they still are”.

The pirates forgive Frederic for his intention to destroy them, admitting that piracy doesn’t pay very well anyway, and Frederic, hating piracy though he does, feels duty bound (as it isn’t yet twelve o’clock) to tell them that they would be far more successful pirates if they would give up their tradition of never molesting orphans. Since this tradition has become known, he points out, everyone they capture claims to be an orphan,  He ingenuously jokes that “one would think Great Britain’s mercantile navy was recruited solely from her orphan asylums – which we know is not the case!” Of course, as Gilbert knew, it very nearly was the case! Frederic tries to persuade the pirates to turn themselves in voluntarily, but the Pirate King replies that while they may be poor, at least their consciences are clear (3). “Contrasted with respectability”, he declares, “piracy is comparatively honest.”

Ruth once again declares her love for Frederic and he, never having seen another woman, agrees to marry her in spite of the difference in their ages. Just at that moment, however, there appears on the scene a bevy of beautiful maidens, the wards of Major-General Stanley, who are out for a day at the seashore. Frederic is immediately captivated by their beauty and, realising  that Ruth has misled him, banishes her (4) from his sight. Hiding in a nearby cave, he watches (5) the girls, but when they remove their shoes with a view of paddling in the sea he is unable to restrain himself and bursts out of the cave, declaring (6) that although he is at present a pirate, he will not be one for long. He attempts to enlist their aid in his plan to destroy the pirates and at the same time declares (7) his love for whichever of them will have him. The girls are indifferent to his plea except for Mabel, who returns his words of love (9) as her sisters tactfully talk about the weather (10).

Frederic warns the girls that the pirates are nearby, but as they prepare to retire (11) the pirates spring into view, seize the girls and threaten them with immediate marriage. They are forestalled only when Mabel reveals (12) the identity of their ‘father’, the Major-General, who at that moment appears and introduces (13) himself. When he learns of the pirates’ intentions he unhesitatingly claims to be an orphan. The pirates are thoroughly disgusted by this news, but after an initial misunderstanding stemming from the similarity of pronunciation of the words “orphan” and “often”, they are touched to the depths of their sensitive souls by the Major-General’s tale of woe. Unaware that it is a lie, they sing a hymn to Poetry (14a) and let him and his daughters go free.

Everyone congratulates Frederic and Mabel on their engagement, and the pirates, who show a remarkable lack of concern over their loss of the girls, are roundly praised (14b) for their gallantry.


 The Major-General, however, is conscience-stricken over his “abominable falsehood”, and sits in the chapel of his recently-acquired medieval castle, humbling himself before the tombs of his “ancestors-by-purchase”. His brooding is interrupted by Frederic, who announces (16) that his band of “lion-hearted” policemen stand ready to do battle with the pirates. As they march in review before the Major-General and his daughters, however, it is quite clear (17) that they are less than enthusiastic about the coming fight, in spite of the girls’ exhortations to them to “go and die”. After they march off to “death, slaughter... glory and the grave”, Frederic is suddenly (18) confronted by his old comrades, Ruth and the Pirate King, who bring news of a “most ingenious paradox” (19) which has just occurred to them. It seems that Frederic was born in a leap year on February 29th. Thus while it is true that he has lived 21 years, at the same time “if we go by birthdays” he is only “five and a little bit over”. Frederic is slow to grasp the implications of this fact until the Pirate King produces a document (!) showing that Frederic was indentured to the pirates not until his 21st year, but until his 21st birthday.

Realising that Duty has once again thrown him in with the pirates, Frederic immediately reveals that the Major-General is not an orphan, and what’s more, “he never was one”. Ruth and the King greet this news with howls of rage and, swearing vengeance (20), they retire, leaving Frederic to the sad task of informing Mabel that the wedding is off. This he does (21), reassuring her, however (22), that “in 1940 I of age shall be”. Mabel replies that although “it seems so long” she will wait for him.

Mabel herself is therefore left to exhort the police to do their duty (23), and they reluctantly agree to fight the pirates, even while lamenting that “a policeman’s lot is not a happy one” (24). Suddenly, they hear the pirates approaching (25) and they conceal themselves. The pirates are out for blood (26) and armed to the teeth, and it seems as if the battle must begin when the Major-General (27) stumbles upon the scene. Unable to sleep, he has left his bed, thinking he “heard a noise”. Satisfying himself that “all is still”, he sings a lullaby (28), awakening his daughters. As they attempt to console him (28a), the pirates attack, the police jump to his defence, and there is a terrific struggle in which the pirates gain the upper hand (28b). The police sergeant, however, in spite of the sword at his throat, charges the pirates to “yield in Queen Victoria’s name.” Dumbfounded, the pirates drop their weapons and surrender, declaring that “with all our faults, we love our queen.”

The Major-General orders their immediate arrest, but Ruth informs him that, far from being common criminals, the pirates are in fact noblemen who have “gone wrong”. This appeal to the Major-General’s reverence for the peerage has its effect (his own ancestors, after all, were only recently purchased) and he excuses the pirates and offers them his daughters in the bargain. The pirates are willing to let bygones be bygones at this point; their change in rank has made them indeed “nice companions for young ladies”, and with the prospect of imminent mass parsonification, (28c) felicity reigns supreme.