1. Pavilion attached to King Hildebrand’s palace
2. Gardens of Castle Adamant
3. Courtyard of Castle Adamant

• King Hildebrand, baritone
• Prince Hilarion, his son, tenor
• Cyril, Hilarion’s friend, tenor
• Florian, Hilarion’s friend, baritone
• King Gama, comic baritone
• Princess Ida, Gama’s daughter, soprano
• Lady Blanche, professor of Abstract Science, contralto

As in all GS works, there are splendid and spirited choruses and ensembles, many of them satirical in character. The scoring testifies to Sullivan’s great skill and at unexpected moments the listener’s heart is touched by delightful lyrical passages. Critics have deemed that the work contains some of the best music Sullivan wrote.

At the age of one Princess Ida was betrothed to the two-year-old prince Hilarion, son of king Hildebrand. The two children grew up apart. When, however, the day comes for the two to be united, Ida appears to have withdrawn in a castle, where she has founded a university for women. No man is allowed to set foot there, but Hilarion and two friends manage to enter, by dressing up as women and registering as students. Alas, they are found out. King Hildebrand now wants to storm the castle so as to liberate his son and force Ida to fulfil her obligations. The women appear to be less warlike than they pretended to be: one by one they forsake Ida. Eventually the haughty princess yields to the argument that, if women renounce men, they may set a glorious example to prosterity, but at the same time seriously endanger prosterity’s existence. All obstacles to a jubilant finale are thus removed.