Documentary dramatic anthology about the U.S. Navy's submarine fleet. All stories were based on fact and the realism was heightened by actual use of combat footage from the files of the Navy. The stories were varied between the South Pacific during World War II and the Korean War. The series was the brainchild of Rear Admiral Thomas M. Dykers, who retired from the Navy in 1949 after 22 years service. The Navy loaned him the U.S.S. Sawfish for the filming of several episodes.