Life is a never-ending search for fun and good times for the sailors lucky enough to be stationed at the naval base located on the tiny Caribbean island of San Ysidro. The biggest disruptions in the lives of sailors Gruber, Christy, Willie, Virgil and Happy are results of bad weather, bad hangovers or the newly-arrived Captain Binghampton's occasional bad-tempered attempts to establish obedience. Most of the guys' days are spent helping their fearless old leader, retired Navy Lt. Commander Quinton Me Hale, spread free enterprise around the nearby islands with a variety of business endeavors, including his trademark beverages, ice cream and pinup calendars. Needless to say, to the local residents of San Ysidro's surrounding islands, the good-natured, big-hearted McHale is a popular guy. He even coaches a little league baseball team. But all of a sudden there seem to be a lot of distractions for the sailors and their former commander-turned-businessman. First, a new by-the-rulebooks crewmember, Ensign Charles Parker, has been nosing around asking a lot of questions. Also, Captain Wallace Binghampton and his beautiful but icy sidekick Lt. Penelope Carpenter have just been assigned command of the base. But these distractions are relatively minor, compared to the machinations of Major Vladakov, a maniac who's invaded one of the nearby islands. Not only is he threatening the lives of its inhabitants, many of whom happen to be close and personal friends of McHale's, but he's putting a major damper on the sailors' laid-back lifestyle. It won't be long before Vladakov discovers that he picked the wrong island to mess with because, much to Binghampton's dismay, McHale is about to come out of retirement. These killjoys don't stand a chance_McHale's Navy is about to rock the boat.