Some people were shocked when Olivier Theyskens told me, after last year’s Met Ball, that he sometimes likes to pee into the Seine. What would they say if they knew the Belgian designer has donned women’s underthings? In her intro to the new book The Other Side of the Picture (Assouline, $150), Vogue’s Sally Singer informs us that, in an early photo shoot, Theyskens wore lingerie belonging to the girlfriend of the man taking the pictures: Julien Claessens. So while the whole world knows of Theyskens’ genius for weirdly romantic clothes, in the tome it’s Claessens on display.

Claessens is not your average backstage shutterbug. His images are the product of a friendship with Theyskens going back to their school days in Brussels, when the two discovered that they shared a dreamy yet morbid sensibility, seen here in the awkwardly stunning images covering 12 collections (for Rochas, Nina Ricci and Theyskens’ own short-lived label). In some, the models look like rare, skinny birds, limbs flailing and bones protruding—Hana Soukupová’s shoulder blades are downright creepy. Yet sadly, because we can’t think of anything hotter that young Olivier in a lacy brassiere, images from that early shoot don’t appear in the book.