A two-person character study directed by John Huston, Heaven Knows Mr. Allison stars Robert Mitchum as a World War II Marine sergeant and Deborah Kerr as a Roman Catholic nun. Both nun and sergeant are marooned on a South Pacific island, hemmed in by surrounding Japanese troops. Mitchum does his best to make the nun's ordeal less painful, but is torn by his growing love for her. Kerr is equally fond of Mitchum, but refuses to renounce her vows. Their unrealized ardor mellows into mutual respect as they struggle to survive before help arrives. Based on a novel by Charles K. Shaw, Heaven Knows, Mr. Allison was coproduced by Eugene Frenke, who later filmed a low-budget variation on the story, The Nun and the Sergeant (62), which starred Frenke's wife Anna Sten.
~ Hal Erickson, All Movie Guide