The detailed design document covers the basic theory, related technique, and implementation details of the MovieOracle system. It first provides a high-level system overview. Then it discusses the usage of Twitter API, Twitter4J and CI-Bayes. After that, it describes how components communicate with each other, how they are organized, and how each of them is implemented. Finally the document introduces the sentiment analysis and the decision tree method of the project. A program implementation for this project should follow the direction of this document.