Taped to the gallery door was a note in agitated ballpoint capitals: DARREN, it warns, THIS PLACE IS UNDER POLICE SERVAILANCE ENTER AT YOUR OWN PERIL. Curiously, though, the anonymous author of this misspelled welcome continues: HOPFULLY ILL BE HERE WE CAN TALK. The found text provides a vivid cue to a scenographic presentation typical of Arps’s recent shows, in which exhibition spaces have been cast, in part through their titles, as bunker, dungeon, and ranch. Here in “Explaining Things,” the windows in the exhibition space were boarded up, and some battered outdoor furniture alluded obliquely