Call to an unknown ship is a visual essay shot as a video in the format of a book. The essay takes as its starting point Philip Hoffman's film ?O, Zoo! shot in The Netherlands in 1985 about the making of Peter Greenaway's film A Zed and Two Noughts. A chance encouter with Hoffman's film during an Internet search for Marcel Duchamp's Etant Donnes sets the narrative in motion. In the pages that follow the essay uses reflection, symmetry and appropriation in a search for what if anything is lost.