These days, no one is surprised if a popular film generates a series of sequels or even prequels, but back in the 1830s the idea of a composer coming up with a sequel to a symphony must have seemed a little odd. But that odd idea did pop into the head of French composer Hector Berlioz.

In 1830, Berlioz had a huge hit with his “Symphonie fantastique.” That “Fantastic Symphony” told a story through music, based on the composer’s own real-life, unrequited love for a British Shakespearian actress. The story ends badly, with our hero trying to end it all with a dose of opium, which, while not killing him, does produce, well, “fantastic” nightmares in which he is condemned to death for killing his beloved who reappears at a grotesque witches’ sabbath.

That seems a hard act to follow, but two years later, Berlioz produced a musical sequel, entitled “Lelio, or the Return to Life,” which premiered in Paris on today’s date in 1832. In this, our hero awakes from his drug-induced nightmare, and, with a little help from Shakespeare and a kind of 10-step arts-based recovery program, rededicates his life to music.

Berlioz intended the original and the sequel to be performed together as a kind of double-feature. Alas, while audiences thrill to the lurid “Symphonie fantastique,” they tend to drift during the admirable, but rather boring rehab sequel, which is rarely performed.