What is the fine-grained topic of the following text: Fans of Marvel films have come to expect a wealth of easter eggs, hidden references and comic book secrets packed into just about every story - and while Thor: The Dark World may have laid the foundation for the future of the movie universe more clearly than any before it, that doesn't mean there weren't subtle inclusions as well. Only return the topic.
Easter eggs and hidden references in Thor: The Dark World movie.