When you've got the Kennedys and the Koch brothers on the same side of an issue, it's hard to know what to think. That's just one of the paradoxes of the Cape Wind clean-energy project, a plan proposed in 2001 to build 130 wind turbines in Nantucket Sound. As related in John Kirby and Robbie Gemmel's rollicking documentary, two groups battled for 10 years over the proposal, one made up of residents who protested the despoliation of their pristine waterway, the other environmentalists fighting for clean energy sources. But who were these groups, really: where did they get their money and what were their agendas? The filmmakers employ the usual talking heads but spice it up with snippets of goofy archival footage that sometimes seem more insipid than ironic. Nonetheless, a dizzying look into the deceptive world of political activism, worth it for a glimpse at the making of a Daily Show segment alone.