a question about a story i am writing

The question concerns the method of foreshadowing future events. When is it good and when it is it revealing too much
theres a young man who will be captured and turned into a feminine sex slave later in the story. I show him going though his life, helping people
I had planed on showing his step mothers moves as she conspires to have him captured later in the story. showing her conspiracy and the people she meets, pays and shows the mechanisms working behind the scenes of his life to rip it apart. It was going to be good

then i started asking myself, i know it is good and i think it adds some suspense but is it foreshadowing too much. Showing he will be captures and how. then why read the story when im showing what will eventually happen

Maybe I shold leave that out and when he is captured, it is more shocking. but Id like to show why and how cruel she is to have this done
The struggle is how he deals with it, and how strong he becomes.
The point of the story is that he is a good caring man who will go out of his way to help people. Which is his downfall. his struggle for freedom and in the end, hes dark and vengeful and cruel just like his step mother. he was made that way
But do the more experienced writers think of the issue