At a party in 1960s New York Adam Walker, a literature student at Columbia and aspiring poet, meets Rudolf Born, a Frenchman who is a visiting professor at the same university. Apparently on a whim, Born, privately wealthy and with shadowy and powerful connections in France, offers Walker the money to publish his own literary magazine and encourages him to seduce the sultry Margot, Born's girlfriend. Walker and Margot promptly sleep together, but it is clear that neither of them is the protagonist of their relationship – it is Born who has seduced them both. On his return from Paris, Born seeks out Walker in New York and as they walk through the city at night a mugger, Cedric Williams, confronts them with a gun, whereupon Born stabs him. Walker runs for an ambulance, but when he returns to the scene of the attack both Williams and Born are gone. Subsequently, Williams's body is found in a nearby park; he has died of more than a dozen knife wounds. 

Invisible, Paul Auster's fifteenth novel, is in four parts. The action above constitutes the first of these, which is described as a work of non-fiction. This part is presented as being the text of a manuscript posted in the present by Walker, now terminally sick, to a university