Allison is wounded by a grenade fragment while disabling the Japanese 105's. But when his bloody shoulder is first seen, the blood stain is visibly too bright for real blood.
The script called for several Japanese-speaking officers and a company of Japanese troops to be on the island. There were no Japanese men on the islands of Trinidad and Tobago, where the film was shot. A half-dozen who spoke the language were finally found in a Japanese emigrant community in Brazil and flown to the location to play the officers. For the non-speaking roles of Japanese troops, the company hired 50 Chinese who worked in the island's restaurants and laundries. This caused friction with the local islanders, who found it difficult if not impossible to get their clothes cleaned or to get a meal in a restaurant because most of the employees were working on the film.