* A book title: There are many books with this title. For example, there's a thriller by James Rollins, a sci-fi novel by James S.A. Corey, and a book about climate change by Paul Hawken. To tell you the theme, I need to know which book you are referring to.
* A TV show episode: There are episodes of TV shows like "The X-Files" and "Doctor Who" titled "Eleventh Hour." Again, I need to know which specific episode to understand the theme.
* A general concept: "Eleventh Hour" can refer to a moment of crisis or a time when something crucial needs to happen.
Please tell me more about which "Eleventh Hour" you're interested in, and I can help you identify its theme.