Pretty good WW2 movie, filled with all the cliches of the era and genre, but good action scenes. No actual war footage but good re-creation(s) given no CGI. Real PT boats used.
During WW2, the US suddenly had the need for a fleet of small attack vessels, the PT-Boats, which gained fame in the Pacific. They were mostly wooden-built, by Elco, Higgins and Huckins.