As Rusesabagina stepped onto the tarmac, a half dozen armed men emerged from the predawn darkness. Identifying themselves as agents of the Rwanda Investigation Bureau — the country’s equivalent of the F.B.I. — they handcuffed him and hustled him into a waiting vehicle. It was only then that Rusesabagina realized that he had fallen into a trap. The plane hadn’t landed in Burundi. Their real destination was declared by a sign on the terminal: KIGALI INTERNATIONAL AIRPORT.