Brian Sanders JUNK takes its 2017 Fringe Festival offering to Grays Ferry Crescent Trail Park, a serene, disconnected portion of the Schuylkill Trail with entrances in three spots around Forgotten Bottom (which, we know, sounds like the name of a sad gay porn). The show, like all of artistic director Brian Sanders’s work, is bizarre, complex and immersive. It’s actually four shows in one. Audiences choose which experience they want to take: the bare-bones Rugged Primal, which includes more of a walking tour; an apocalyptic-themed excursion called Nuclear Romance; “courly romp” Medieval Revelry; or Future Fancy Ultimate, a more stationary performance that includes a picnic dinner. At the end of each performance, the audience converges in an open field in the center of the park at sunset for a dazzling grand finale that incorporates JUNK’s signature acrobatic moves, song and a lot of rolling around gracefully in the grass.