The Grateful Dead's new documentary, "Long Strange Trip" is coming out next month. The four-hour flick was produced by Martin Scorsese, and covers the Dead's career and the death of frontman Jerry Garcia. In a new interview, drummer Mickey Hart revealed that the film was tough to watch saying, "It's charming and it's heartfelt. But it's sad in some ways. It's not a date movie." Guitarist Bob Weir agrees but said the uplifting overtone of the film overrides the somber moments. Weir claims, "A lot of the stories in the film are fairly dark, but there's a light that shines above all of that. [It's] counterbalanced by the music itself."