There have been a couple of important developments on the subject of Canadian hydropower since we released our 4-part series, Powerline. Today, we bring in NHPR's environmental reporter, Annie Ropeik, and our executive producer, Erika Janik, to talk about Northern Pass and the future of energy projects in New England. Plus, we look back at a handful of older episodes to see what has changed since we first put them out.  Beaver deceivers? Kiwi-berries? Crazy trail crew stories? Prepare to have your brain updated.