When a Soviet submarine gets stuck on a sandbar off the coast of a New England island, its commander (Theodore Bikel) orders his second-in-command, Lieutenant Rozanov (Alan Arkin), to get them moving again before there is an international incident. Rozanov seeks assistance from the island locals, including the police chief (Brian Keith) and a vacationing television writer (Carl Reiner), while trying to allay their fears of a Communist invasion by claiming he and his crew are Norwegian sailors.