The novel's anti-hero is Sir Roy Vandervane, a late middle-aged orchestral conductor and composer.
The novel is narrated by his friend and colleague Douglas Yandell, whose love life is hardly less complex.
Sylvia is Sir Roy's (much) younger girlfriend with wisdom and guile far beyond her years.
The plot describes the interactions of the aforementioned and of wife Kitty and daughter Penny.
You can help Wikipedia by expanding it.See guidelines for writing about novels.