When HMS Scotia pays a visit to the French Riviera, the officers throw a lavish party to celebrate the engagement of Captain Robert Randall to Jill Eaton, a charming American girl; among the guests are Mary Carlton, Jill's American friend, and Antoinette, a vivacious redhead. However, when the last shore-boat is deemed unseaworthy, the girls are obliged to spend the night on ship. A series of hilarious complications ensue, as the officers attempt to keep the girls away from the beady eyes of Admiral Hewitt – who chooses this very night to board the Scotia.
