Often the introduction to an Annotated Bibliography on a literary topic may contain:
1.) A question for research and working thesis or hypothesis;
2.) Key ideas/quotes from the primary text or a major source;
3.) Your planned scope of research; and
4.) Further ideas and hopes for the paper. It may include a stab at a conclusion, your initial attempt to answer your thesis.
Since you are still in the process of researching, this is usually termed a "working" thesis.
This 6 minute video will demonstrate the development of an introductory paragraph:
