"Back to the Future Part II," released in 1989, is the sequel to the original "Back to the Future" film. It follows Marty McFly and Doc Brown as they travel to the future (2015) and back to 1955 to prevent a disastrous timeline. The movie is part of a trilogy, with the third installment, "Back to the Future Part III," released in 1990. There are no plans for a new sequel, but the original films remain iconic, with a dedicated fan base and ongoing discussions about potential reboots or adaptations in various formats.

In "Back to the Future Part II," the timeline includes a visit to the future, specifically to October 21, 2015, rather than July 3, 2025. The film depicts various futuristic technologies and scenarios that were imagined for that year. The movie doesn’t specifically reference July 3, 2025. Instead, it focuses on events occurring in 1985, 1955, and the future of 2015, showcasing the adventures of Marty McFly and Doc Brown as they navigate time travel.

Crispin Glover did not return for "Back to the Future Part II" due to a contract dispute. He was not satisfied with the terms offered for the sequel and wanted a higher salary. Additionally, the filmmakers opted to use archival footage of his character, George McFly, from the first film, along with a different actor, Jeffrey Weissman, who was made up to resemble Glover. This decision led to controversy and legal issues, as Glover later sued the filmmakers for using his likeness without permission.

In "Back to the Future Part II," Marty's girlfriend Jennifer Parker was replaced due to scheduling conflicts with actress Claudia Wells. Wells was unable to reprise her role because she was committed to another project. As a result, actress Elisabeth Shue was cast to play Jennifer in the sequel. The change was not addressed in the film, leading to some confusion among audiences, but Shue's portrayal fit well within the story as the timeline continued to unfold.