What is the most successful sequel?

I'm curious, can you enlighten me on the matter of sequels in the realm of media? Specifically, which sequel stands out as the most triumphant and successful, captivating audiences and surpassing its predecessor in every way? Is it a movie that deftly continues the narrative in a captivating manner, a game that expands the world and storyline to new heights, or perhaps a book that takes the characters and themes to unimaginable depths? What are the defining characteristics that have led to its unprecedented success?