A Dutch conceptual artist, performance artist, photographer and filmmaker, Ader (1942–1975) spent the last 12 years of his life in Los Angeles as part of a scene that included John Baldessari, Allen Ruppersberg and William Leavitt. Much of his work involved the sort of bare-bones body art prevalent at the time, especially in the form of stark videos in which he could be seen crying, falling off a roof, dangling above a stream from a tree branch before plunging into the water, and trying heft a large stone in a small garage. As these descriptions indicate, Ader’s work was darkly existential, filled with a sense of loss that may have been rooted in his childhood experience in Holland, where the Nazis executed his father in 1944 for helping Jews to escape. Ironically enough, his death was consistent with the tone of his work, as he perished at sea in 1975 during one-man voyage across the Atlantic undertaken as part of an art project. This shows presents key works from the early ’70s, including never-exhibited selections.