This is a sort of briny equivalent of out of the frying pan and into the fire, as "Leach" (John Garfield), "Ruth" (Ida Lupino) and "Van Weyden" (Alexander Knox) find themselves unwilling passengers on a schooner. It's skipper "Larsen" (Edward G. Robinson) must have gone to the William Bligh school of seamanship as he rules his vessel with a ruthless rod of iron. What begins to puzzle our reluctant passengers is just what the ship's mission is and why their host refuses to drop them off at any port but, eventually, at their home of San Francisco. As that mystery deepens, we become immersed in…