No, not your problem, per se - the problem of your main character. The biggest issue I find when reading queries, and the reason why I choose not to request more material, is that I just can't figure out what the central conflict of the plot is.
So sit down, Authors, and think: What does my main character need to accomplish? Is there a problem that he/she needs to solve? Sure this may sound a bit formulaic. It is. If your story is more character driven, you may need to approach this differently. But for those of you who are writing high-concept manuscripts, really think about it. If you don't know, then you really do have a problem.
PS: A secret revealed is not, and cannot, be the plot. For example, the plot of Harry Potter isn't that he learns he's a born wizard. It's that he must defeat Lord _______ (hey, I'm superstitious). See? Maybe the reveal of the secret is the impetus for the rest of the novel; if so, tell me what comes next. How does this change the character's life?