It's 1930. Claire (Liza Minnelli), an American living in Tijuana, Mexico, has just buried her husband Harry, who owned a dive bar there. Walker Ellis (Burt Reynolds), a loser with whom she has long had a thing on the side, agrees to wrap up her affairs in Tijuana for her so that she can move stateside before they be together after an appropriate grieving period. Wrapping up those affairs includes smuggling one last truckload of illegal Mexican immigrants across the border. In that job not going quite according to plan, Walker is forced to go into business rum running across the border with Kibby Womack (Gene Hackman), one of those he was trying to smuggle across the border, Kibby an American in trouble with Uncle Sam. Instead of via overland, Walker has hired Billy Mason (Robby Benson) to Captain the sailboat to transport the goods via water, Billy a young, quiet man unwise to the ways of the world, but wise when it comes to the sea. As Walker, Claire, Kibby, and Billy navigate the waters on this venture, they will find two inherent risks. The first is the U.S. Coast Guard, officious Captain Moseley (Geoffrey Lewis), who patrols these waters. Moseley and the Coast Guard can do nothing if they're in international waters unless there is a sign of illegal cargo or a sale of illegal merchandise. As such, Moseley can usually just "starve" rum runners who just sail up and down the coast unable to dock in a U.S. port. And second is other rum runners. While the small players generally leave each other alone, the east coast mob has sent Christie McTeague (John Hillerman) to place first a foothold then second a stranglehold on the entire west coast Mexico-U.S. trade. Through it all, Claire has convinced Kibby and an initially reluctant Walker that their three partner business should extend into the bedroom.