“A photograph is a secret about a secret,” said Diane Arbus. “The more it tells you the less you know.” A major solo exhibition on Arbus, the first in Canada in almost 30 years, covers the astonishing work she produced from 1956, when she left commercial photography to pursue her own vision, to 1971, the last year of her life, which ended in suicide. Not least of the secrets is that pervasive, off-kilter, Arbusean atmosphere—filling one frame after another no matter the subject—and how she always found it. —L.J.