and happy cruisers not so happy. cruises are the fastest-growing vacation segment in the industry that brings in billions of dollars a year. but a string of high-profile mishaps is raising some troubling questions about regulations for cruise ships. how safe are they? and who do the cruise lines actually answer to when things go wrong? special investigative correspondent drew griffin has been looking into it. >> reporter: deadly crashes. >> a smoke situation. >> reporter: stalls. fires. >> not a drill. not a joke. >> reporter: what is going on with cruise ships? what is going wrong? according to critics of the cruise industry, like maritime attorney jim walker, we may never know because companies register most of their ships in small countries across the globe. they are, he says, very reluctant to tell the public or the u.s. government much of anything.