Jennifer Garner and David Tennant star in HBO's Camping as Kathryn and Walt, a not-so-happily married couple. A meticulously planned outdoor trip to celebrate Walt's 45th birthday is derailed by uninvited guests and forces of nature, turning the weekend into a test of marriage and friendships. The limited series hails from Girls executive producers Lena Dunham and Jenni Konner, and premieres October 14 at 10 p.m. on HBO.