The bonus material included in the Back to the Future 25th-anniversary box is generous and varied, offering items that are exclusive to Blu-ray by way of Universal's interactive "U-Control" pop-up features, which viewers can access at any point while watching the trilogy. These features include "Setups & Payoffs," which explain the connections between various scenes throughout the three films (for example, in the opening credits of the first installment, the camera pans over a room filled with clocks, one of which has a miniature man dangling from its hands--a tableau revisited later); a trivia track; access to storyboards to watch while the finished scene is onscreen; and a bookmarking option. All make good use of at least some of the Blu-ray format's vast potential.
Elsewhere, the main attraction is likely to be Tales from the Future, a newly made, nearly three-hour documentary in six parts (three on the first disc, one on the second, and two on the third). Most of the principals from both behind the camera (director Robert Zemeckis, producer Bob Gale, exec producer Stephen Spielberg, etc.) and in front of it (actors Michael J. Fox--Parkinson's disease notwithstanding--Christopher Lloyd, Lea Thompson, and others) are on hand to discuss the Back to the Future odyssey. There are some fascinating revelations throughout--not least the facts that Eric Stoltz, not Fox, was first cast in the Marty McFly role, only to be replaced after five weeks of filming (a few of Stoltz's scenes are shown here), and that the filmmakers rejected Crispin Glover's excessive demands for Back to the Future II, which led to his role as McFly's father being written out of the story. Other extras include "archival" making-of featurettes, which offer some of the same material as the newer documentary (and delivered by many of the same folks, only considerably younger), while a featurette on the second disc in which theoretical physicist Michio Kaku discusses the physics of time travel in the films is also quite entertaining.
Each disc also includes deleted scenes, audio commentary tracks with Gale and coproducer Neil Canton, a Q&A commentary track with Zemeckis and Gale, and a host of "behind-the-scenes" material explicating everything from makeup tests, outtakes, and storyboards to effects shots and the creation of the DeLorean "time machine." And that's not all: in addition to common ingredients like photo galleries and theatrical trailers, viewers wanting to go back to the past can dial up music videos by Huey Lewis and the News and ZZ Top from the first and third films, respectively.