Castor dwelling in the happy shades is giving himself up to the charm of the Elysian fields and to melancholy thoughts of his earthly loves. Neither the fair prospect of a return to life, nor the pain that he feels on hearing that his brother, his liberator, is his rival, disturbs his sense of honour. He will not consent to the death of Pollux. He agrees to return to earth for one day only; Mercury transports him thither. The extreme shortness of his happiness dashes with sadness the tender words that he exchanges with Telaïre in a pleasant Spartan glade. But as he is preparing to descend again to the shades, songs of joy burst forth. Jupiter, satisfied with the test, restores both brothers to life, and to reward their devotion promises that they shall have their place among the stars.
The poet Bernard has handled this theme in sparkling—often too sparkling—verses of the minor school of the 18th century, and in style that smacks of Ariosto rather than Racine—not that we would bring that up against him, for Ariosto may well be called the greatest of the poets of opera. Yet there is in Castor much that recalls Racine but it is Rameau's music that puts it there.
The interludes, dances and figures led up to by the development of the subject are as follows: in the first act the entrance of athletes and warriors, who celebrate by their games and songs the victory of Pollux over Lincée: in the second, the entrance of Hebe at the head of the Celestial Pleasures, holding in their hands garlands of flowers with which they seek to bind Pollux; in the third the choruses and sarabands of demons who, to frighten Pollux, "emerge from the lower world through flames:" in the fourth the singing ballet of the Happy Shades; in the fifth, by way of finale, the gathering of "stars, planets, satellites and gods" celebrating the glory of their new colleagues, Castor and Pollux.
