American Caesar by William Manchester (1978). The definitive biography of Douglas MacArthur, covering his time in the Philippines in detail — his command from Corregidor, his departure by PT boat in March 1942, and his eventual return. Dense and opinionated, it gives the figure who haunts the island its full human complexity.
Ghost Soldiers by Hampton Sides (2001). The story of the Bataan Death March and the survivors who were held as POWs for three years, and the extraordinary Ranger raid that freed them. Corregidor is the opening act of this story, and Sides writes it with the pace of a thriller. Probably the most readable entry point to the whole campaign.
The Rising Sun by John Toland (1970). A Pulitzer-winning history of Japan's war in the Pacific told largely from the Japanese perspective. Corregidor appears from the other side of the siege — the view from the Japanese commanders planning the assault. Reading it before or after a visit adds a dimension the tramvia tour can't quite provide.
In Our Image: America's Empire in the Philippines by Stanley Karnow (1989). A Pulitzer-winning history of the American relationship with the Philippines from 1898 through independence. Corregidor sits near the centre of this history, and Karnow's book explains why the island mattered beyond its military value — and why the fall still resonates in Philippine memory.